The History of Gems, Jewelry and Precious Metals

The Bizmoune Cave shell beads (at least 142,000 years ago)

Bizmoune Cave is a cave near Essaouira, in southwest Morocco. Between 2014 and 2018 a joint Moroccan and international team dug out 33 shell beads there. All but one are the sea snail Tritia gibbosula, and some still carry traces of red pigment. When the team published them in 2021 they called them the oldest shell beads yet recovered. The authors read such beads as signals of identity, a sign that people were already using ornaments to show who they were.

How it was made and found: The shells are marine, and most of the holes are partly natural but many show signs of human modification such as chipping. Seventy-five percent of the shells show polish and fine scratches in the aperture, the wear you would expect from hanging on a cord. The team dated a cave-mineral growth (speleothem) near the beads with uranium-series dating, which gave about 142,000 years.

Where it is now: The beads were published in Science Advances in 2021 and are known mainly through that paper. The date is still being argued. The authors themselves note that luminescence dates from the same layer came out younger than the uranium-series dates, and they call the mismatch unresolved.

• Of the 33 beads, all but one came from a single layer, called 4c. The layer is about 50 to 100 centimetres thick.
• Seventy-five percent of the shells show polish and fine striations inside the aperture, the wear pattern that points to use as ornaments rather than damage from the soil.
• Some of the shells carry traces of red pigment. Small blocks of red pigment and ochre residues turned up in the same layer on stone tools and pebbles.

On The Gem Tray: How ancient people drilled beads and worked stone by hand

Sources: Sehasseh et al., Early Middle Stone Age personal ornaments from Bizmoune Cave, Essaouira, Morocco, Science Advances 7(39), 2021 (open access, PubMed Central); Aberystwyth University research record for the Bizmoune Cave paper; Nature Middle East: Moroccan cave reveals world's oldest shell beads (22 September 2021); Wikipedia: Tritia gibbosula

The Skhul and Qafzeh shell beads (c. 135,000 to 92,000 years ago)

Skhul and Qafzeh are caves in northern Israel that held burials of early modern humans. Both sites also gave up sea shells that had been carried to them. At Skhul, two perforated shells of the marine snail Nassarius gibbosulus were identified in museum collections in 2006. At Qafzeh, ten Glycymeris clam valves with natural holes were brought from the Mediterranean shore, some 35 kilometres away according to the excavators. Together they show people choosing shells for the body well before the famous European cave art.

How it was made and found: One of the two Skhul shells carried a crust of sediment that was analysed at the Natural History Museum, London, and tied it to the layer that held human skeletons dated to 100,000 to 135,000 years ago. A 2006 study in Science reported the Skhul shells alongside a similar shell from Oued Djebbana in Algeria. At Qafzeh, the lower layers are dated to about 92,000 years by the excavators, and several valves bear traces of having been strung, with a few showing ochre stains.

Where it is now: The beads are archive material today: the Skhul shells are kept at the Natural History Museum, London, and are studied rather than shown as a treasure. Scholars still argue about how deliberate the earliest shell use was. Older Glycymeris shells at Misliya Cave, from about 240,000 to 160,000 years ago, were carried in but were not perforated.

• The Oued Djebbana site in Algeria lies about 200 kilometres from the sea, so the researchers argued the shells must have been carried there on purpose.
• A 2020 study concluded that between about 160,000 and 120,000 years ago people in the Levant shifted from collecting whole, unpierced shells to collecting shells with holes that could be strung.
• The Skhul bead was found by searching museum collections, not by digging. The researchers went back through old finds and recognised the shells as beads.

On The Gem Tray: How ancient people drilled beads and worked stone by hand

Sources: Bar-Yosef Mayer, Vandermeersch and Bar-Yosef, Shells and ochre in Middle Paleolithic Qafzeh Cave, Israel, Journal of Human Evolution 56 (2009); Bar-Yosef Mayer et al., On holes and strings: earliest displays of human adornment in the Middle Palaeolithic, PLOS ONE (2020); ABC Science: Shell beads suggest new roots for culture (2006); Wikipedia: Skhul and Qafzeh hominins

The Blombos Cave shell beads (c. 75,000 years ago)

Blombos Cave overlooks the Indian Ocean on South Africa's southern Cape. In 2004 Christopher Henshilwood's team reported 41 perforated shells of the estuary snail Nassarius kraussianus from its Middle Stone Age layers. Thirty-nine came from one phase, dated to about 75,600 years ago. The paper noted that the earliest undisputed African ornaments were 13 ostrich eggshell beads from Kenya, about 40,000 years old, so the Blombos shells were about 35,000 years older.

How it was made and found: The team argued the shells could not have arrived by chance. The snails live in estuaries, the nearest about 20 kilometres away, the shells are all adults, and 88 percent have a hole near the lip, a pattern the paper found in only 8.6 percent of naturally pierced shells. Microscopic wear is consistent with rubbing against thread, clothes or other beads. Ochre residues inside the shells suggest the beads or their cord were coloured red.

Where it is now: Digging at Blombos continues, and since 2017 the site has been excavated under the SapienCE centre at the University of Bergen. Later counts run past 65 beads. The same cave also gave up engraved ochre, and in 2018 a stone fragment with nine red ochre lines dated to about 73,000 years ago, described as the oldest known abstract drawing.

• The shells were found in clusters of 2 to 17 beads, each cluster in the same patch of floor. Within a cluster the shells share a similar size, shade and wear, so each may be the remains of one string.
• Beads from the Middle Stone Age layers are dark orange or black, while beads from much later layers in the same cave are white or pale beige, and the older beads are significantly larger.
• The tiny shells are too small to be leftover food, and the only known predator of the snail, another gastropod, lives only in estuaries, so the authors judged that animals did not bring them to the cave.

On The Gem Tray: How ancient people drilled beads and worked stone by hand

Sources: Henshilwood, d'Errico, Vanhaeren, van Niekerk and Jacobs, Middle Stone Age shell beads from South Africa, Science 304 (2004), p. 404; The Conversation: What excavated beads tell us about the when and where of human evolution (2016); Wikipedia: Blombos Cave

The Sungir burials (c. 34,000 years ago)

Sungir, near the Russian city of Vladimir, is a hunter-gatherer site with some of the richest Ice Age graves in Europe. One grave holds a man of about forty. Another holds two boys of about 10 and 12, laid head to head. The boys' bodies were covered in thousands of ivory beads, and the graves also held ivory spears, armbands, carvings and hundreds of pierced fox teeth.

How it was made and found: Archaeology magazine, reporting a 2018 re-study, counts more than 10,000 mammoth ivory beads with the boys; Wikipedia counts more than 13,000 at the site and says they would have taken about 10,000 working hours to make, which is an estimate, not a measurement. The graves were found in 1955 and dug in the mid-twentieth century. Early radiocarbon dates on the bones were too young, probably because of conservation products on them; a 2014 study of dates on the amino acid hydroxyproline put the site's occupation at about 38,900 to 33,590 years ago, and the 2017 genome paper uses about 34,000 years.

Where it is now: The remains have been re-studied several times. A 2018 re-analysis by Erik Trinkaus and Alexandra Buzhilova found that the children had been through periods of nutritional stress, and that the 12-year-old appears to have been bedridden. In 2017 a genome study found that all the Upper Palaeolithic individuals tested were male and that none was closely related to another.

• The two children were long described as a boy and a girl, and some accounts call them twins. The 2017 genomes showed that both were male, and that although they shared mitochondrial and Y-chromosome lineages, they were not closely related (third degree or closer).
• Beside the boys lay the thigh bone of an adult, filled with red ochre; its DNA matched the boys' mitochondrial lineage. The 2018 re-study also describes two human fibulas laid across the boys' chests.
• The boys' grave goods included more than 20 armbands, some 300 pierced fox teeth and 16 ivory spears, according to the 2018 re-study as reported by Archaeology magazine.

On The Gem Tray: How ancient people drilled beads and worked stone by hand

Sources: Sikora et al., Ancient genomes show social and reproductive behavior of early Upper Paleolithic foragers, Science (2017), author manuscript (University of Cambridge repository); Nalawade-Chavan, McCullagh and Hedges, New hydroxyproline radiocarbon dates from Sungir, Russia, PLOS ONE (2014); Archaeology magazine: Scholars Analyze Russia's Sunghir Burials (14 February 2018); Wikipedia: Sungir

The Çatalhöyük obsidian mirrors (c. 7000 to 6000 BC)

Çatalhöyük was a large farming town on the Anatolian plateau. UNESCO dates the eighteen levels of its eastern mound to between 7400 and 6200 BC, and its western mound to 6200 to 5200 BC. Its people worked obsidian, the black volcanic glass, into blades and arrowheads and traded it widely. A few pieces were ground and polished into slightly convex disks that give a clear reflection. James Mellaart, who found the site in 1958, published pictures of at least six and gave the conventional explanation that a woman used one to look at her make-up.

How it was made and found: In December 1999 the obsidian specialist James Vedder began to copy one by hand. He ground a broken obsidian nodule on a piece of concrete sidewalk, then a discarded abrasive wheel, a fine whetstone and clay slip on plate glass, and later tried granite, quartzite, sandstone, slate, marble, sand, clay and wood ash. His mirrors gave good images and were all slightly convex, like the originals, and he concluded that no technological innovation was needed to make them. In August 2000 he saw eight of the Çatalhöyük mirrors in museums in Konya and Ankara.

Where it is now: The mirrors are in Turkish museums, in Konya and Ankara. Their purpose is still open. Alongside Mellaart's make-up explanation, scholars have proposed uses from lighting rooms to starting fires, signalling, or ritual, but none is confirmed. A 2022 study of pigments in the burials found red and blue pigment on one of two mirrors placed with a child, and iron oxide on a mirror with an adolescent.

• Vedder could not estimate how long the final polish would take, but he noted that grinding and polishing stone were already well established in the Neolithic, and that the only local materials at Çatalhöyük were clay, marl, grasses and hide, so grinding stones would have come from a distance.
• Naomi Hamilton's unpublished inventory of the objects in the Konya and Ankara museums lists 11 items as mirrors or possible mirrors. Vedder verified that eight of the 11 are mirrors and rejected two.
• Mellaart found the site in 1958 and dug it from 1961 to 1965. Ian Hodder's team resumed excavation in 1993, and UNESCO listed the site in 2012. Vedder noted in 2001 that the recent digs had found no mirrors.

On The Gem Tray: How ancient people ground, drilled and polished stone

Sources: UNESCO World Heritage: Neolithic Site of Çatalhöyük (listing 1405); James F. Vedder, Grinding it Out, Archaeology magazine (2001); Schotsmans et al., New insights on commemoration of the dead through mortuary and architectural use of pigments at Neolithic Çatalhöyük, Scientific Reports (2022); World History Encyclopedia: Çatalhöyük

Hongshan jade (c. 4700 to 2900 BC)

The Hongshan culture lived in the Liao River basin of northeast China. The Japanese archaeologist Torii Ryuzo found its type site, Hongshanhou, in 1908. Its richest remains are at Niuheliang, a ceremonial complex with an underground temple, stone cairns and tombs, many of them holding jade. The carved jades include coiled 'pig dragons', for which Hongshan is best known.

How it was made and found: A 2010 PNAS paper by Peterson and colleagues summarises that central crypts and smaller slab graves held offerings almost exclusively of jade: carvings of supernatural themes, bracelets, cuffs, hair tubes and ear ornaments, with no utilitarian objects. Scholars infer ritual specialists, and the elite are often described as ranked by religion more than by wealth. The jade found at Yuanbaoshan is mostly tremolite from Xiuyan in Liaoning, in yellow-white, yellow-green and dark green shades.

Where it is now: Two C-shaped dragons were found by farmers, a yellow jade one in 1949 and a jasper one in 1971, and they now sit in the Wengniuteqi Museum and the National Museum of China. In July 2024 excavators at Yuanbaoshan in Inner Mongolia uncovered a tremolite jade coiled dragon 15.8 centimetres high that they call the largest and best preserved of its kind.

• Since June 2024, more than 100 jade artifacts have been unearthed from the Yuanbaoshan mound tombs, according to the UNESCO Courier.
• The Niuheliang 'Goddess Temple' is named for a clay female head with eyes inlaid with jade.
• The PNAS survey estimated district populations of about 100 to 400 or 500 in the Chifeng area and about 100 to perhaps 700 around Dongshanzui, far short of the thousands sometimes imagined for the culture's core zone.

On The Gem Tray: Jade: nephrite vs jadeite, and how to buy real jade

Sources: Peterson, Lu, Drennan and Zhu, Hongshan chiefly communities in Neolithic northeastern China, PNAS 107(13) (2010); UNESCO Courier: Archaeological discovery of the Hongshan culture jade dragons (2025); Wikipedia: Hongshan culture

Lapis lazuli from Badakhshan reaches Mehrgarh (by c. 4650 to 4000 BC)

Lapis lazuli is a blue rock flecked with gold-coloured pyrite. Mehrgarh, a farming village in Balochistan, Pakistan, has lapis, turquoise and shell ornaments in its burials, and Wikipedia's summary of the excavations says the lapis came from as far away as Badakhshan in Afghanistan. Several lapis beads are reported from the site's Period II (about 4650 to 4000 BC), and a bead workshop of about 4000 to 3500 BC excavated by Catherine and Jean-Francois Jarrige shows a lapis lazuli bead industry. World History Encyclopedia notes that Egypt and Mesopotamia prized lapis, and that scholars knew it came from the east but did not know precisely where until the Indus Valley sites were investigated. Pliny the Elder's 'sapphirus', a blue stone spotted with gold and best from Media, is lapis according to his English translators, and the spots are probably iron pyrite.

• Pliny's 'sapphirus' of the first century AD was, according to his English translators, probably lapis. The word 'sapphire' later moved to the blue corundum we use it for today.
• At Mehrgarh, the amount of burial goods decreased over time, becoming limited to ornaments, and more goods were left with female burials.
• A lapis workshop at Mehrgarh, area MR.2, dated roughly 4000 to 3500 BC, was excavated by Catherine and Jean-Francois Jarrige; the pieces shown from it are a sample of its lapis lazuli industry.

On The Gem Tray: Lapis lazuli in ancient Egypt: where it came from and how it travelled

Sources: Pliny the Elder, Natural History 37.39 (Bostock and Riley translation, Perseus Digital Library); The Human Journey: Lapis, turquoise and beads at Mehrgarh; Harappa.com: Early Evidence of Bead-Making at Mehrgarh, Pakistan (tribute to Catherine and Jean-Francois Jarrige); World History Encyclopedia: Indus Valley Civilization; Wikipedia: Mehrgarh

The Varna Necropolis gold (c. 4600 to 4340 BC)

The Varna cemetery lies on Bulgaria's Black Sea coast. Its graves belong to a Copper Age farming society. A builder's excavator found it by accident in October 1972, and the digs then opened 294 graves holding about 3,000 gold objects that weigh roughly 6 kilograms in total. Beads, rings and appliqués were buried with the dead, and the wealth was concentrated in a few graves.

How it was made and found: The best-known burial, Grave 43, was unearthed in 1974. It held a man of about 40 to 45 with about 1.5 kilograms of gold, including decorations for a bow, together with copper and stone axes and a copper chisel. Some scholars call him a ruler or king-priest; Wikipedia says the view that he was a smith, because of the copper tools, has replaced that reading.

Where it is now: The finds are displayed at the Varna Archaeological Museum and in the National Historical Museum in Sofia. A 2018 radiocarbon study with 71 new dates from 53 graves puts activity at the cemetery between about 4596 to 4516 and 4427 to 4341 BC. The label 'oldest gold in the world' is a claim: other Bulgarian sites such as Hotnitsa, Durankulak and Provadia are nearly as old.

• About 30 percent of the cemetery's estimated area is reported to be unexcavated, according to Archaeology in Bulgaria.
• Radiocarbon work with 71 dates from 53 graves suggests the cemetery was in use for only about 120 to 260 years.
• The excavator operator who first hit the graves in October 1972 was Raycho Marinov, who took some pieces home in a shoe box and reported them a couple of days later. According to Wikipedia, Dimitar Zlatarski, a local museum founder who was called to look at the find, recognised its importance and contacted the Varna museum.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: Higham, Slavchev, Gaydarska and Chapman, AMS Dating of the Late Copper Age Varna Cemetery, Bulgaria, Radiocarbon 60(2) (2018); Archaeology in Bulgaria: Varna Gold Treasure and Varna Chalcolithic Necropolis; Wikipedia: Varna Necropolis

The Nahal Mishmar hoard (c. 4500 to 3500 BC)

On 22 March 1961 the Israeli archaeologist Pessah Bar-Adon entered a cave in the cliffs above the Nahal Mishmar riverbed in the Judean Desert, a cave now called the Cave of the Treasure. His team first found about fifty copper vessels, then textiles, and then the number of copper objects rose past four hundred. Wikipedia counts 442 objects in all, 429 of them copper or bronze, including 240 mace heads, about 100 scepters and 5 crowns. Others are ivory and stone.

How it was made and found: Many of the objects were cast by the lost-wax method: a wax model was covered in clay, the wax melted out, and molten copper poured in. The PLOS ONE paper on the Tel Tsaf awl notes that the casters mixed copper ores high in antimony or nickel with arsenic-rich ores, that reliable radiocarbon dates put the manufacture of these prestige items as early as 4350 to 4250 cal BC, and that petrography of the clay cores suggests the casting took place locally in the southern Levant. Wikipedia says the copper was probably mined at Wadi Feynan.

Where it is now: Prominent finds from the hoard are on display at the Israel Museum in Jerusalem, and a replica crown is at the Hecht Museum in Haifa. What the hoard was is not known for certain. David Ussishkin proposed that the objects were the cult furniture of the nearby Chalcolithic temple at Ein Gedi, moved to the cave for safekeeping.

• Excavators first found about fifty copper vessels, then textiles, and then the count rose past four hundred. The objects were wrapped in a woven reed mat, and radiocarbon dating of the mat points to about 3500 BC.
• Object counts differ by source. Wikipedia lists 442 objects, 429 of them copper, while other accounts say 'over 400'.
• A copper awl from a burial at Tel Tsaf, dated to the late 6th millennium BC, is the earliest metal artifact known in the region, centuries older than the hoard's prestige objects. Its chemistry points to a distant source, probably in the Caucasus, and the authors read metallurgy as arriving in the southern Levant through exchange before local production began.

On The Gem Tray: Copper jewelry: why it turns skin green and how to care for it

Sources: Garfinkel, Klimscha, Shalev and Rosenberg, The beginning of metallurgy in the southern Levant: a late 6th millennium CalBC copper awl from Tel Tsaf, PLOS ONE 9(3) (2014); Institute for the Study of the Ancient World (NYU): Masters of Fire, Copper Age Art from Israel, introduction; Wikipedia: Nahal Mishmar

Ötzi's copper axe (c. 3300 BC)

Ötzi the Iceman was found on 19 September 1991 by two German hikers, Helmut and Erika Simon, near the Tisenjoch pass in the Ötztal Alps, on the Italian-Austrian border. Among his belongings was an axe with a yew handle about 60 centimetres long and a blade about 9.5 centimetres long, made of almost pure copper. The 2017 PLOS ONE paper calls it the oldest axe found complete with its copper blade, hide strips and wooden handle, which is why it could be dated carefully.

How it was made and found: The blade was cast in a two-part (bivalve) mould and never hardened by hammering, so it was used soft. Radiocarbon dating of the handle gives 3350 to 3000 BC. In 2017 Gilberto Artioli's team measured lead isotopes in a sample of the blade and matched them to ore in southern Tuscany. The paper notes that Alpine copper sources were known and in use at the time, but the Iceman's metal did not come from them.

Where it is now: Ötzi died around 3230 BC. An arrowhead was found embedded in his left shoulder, and researchers believe he was killed by another person. He and his belongings have been on show in the South Tyrol Museum of Archaeology in Bolzano since 1998. A 2024 project listed in the museum's research milestones found that other Late Neolithic axe blades north and south of the Alps were also made of Tuscan copper, so the Iceman was not an isolated case.

• Researchers had suspected the copper came from known ore deposits 100 kilometres or less from where he was found, according to Science News.
• It is unclear whether Ötzi acquired the copper as raw metal or as a finished blade, and the paper says it cannot be shown that the axe was made in the Tuscan area itself.
• The blade has about 0.44 percent arsenic (4,360 parts per million) and about 0.1 percent silver (956 ppm), plus small amounts of more than a dozen other elements. That chemical signature, with the lead isotopes, is what let the researchers trace it.

On The Gem Tray: Copper jewelry: why it turns skin green and how to care for it

Sources: Artioli et al., Long-distance connections in the Copper Age: new evidence from the Alpine Iceman's copper axe, PLOS ONE 12(7) (2017); Science News: Copper in Ötzi the Iceman's ax came from surprisingly far away (14 July 2017); South Tyrol Museum of Archaeology: Milestones in Ötzi research; Wikipedia: Ötzi

Liangzhu jade cong and bi (c. 3300 to 2300 BC)

Liangzhu was a rice-farming society in the Yangtze delta, dated by UNESCO to about 3300 to 2300 BC. It built a walled city, a water-conservation system of dams, and cemeteries that UNESCO describes as socially graded. Its most famous objects are jade cong, tubes square outside and round inside, and bi, flat discs with a central hole. World History Encyclopedia says Chinese jade working reached its height in the Liangzhu period.

How it was made and found: World History Encyclopedia says jade (nephrite) was first worked into recognizable objects in China about 6000 BC, in the Houli culture. At Liangzhu it became a mark of status. According to Wikipedia, more than 3,000 jade pieces were excavated at the Fanshan site in 1986. UNESCO lists the jade artefacts as symbols of the society's belief system.

Where it is now: The city was abandoned after about 2300 BC; Wikipedia says extensive flooding linked to climate change is the likely cause, and World History Encyclopedia also points to flooding, which buried and so preserved many jades under silt. UNESCO inscribed the archaeological ruins of Liangzhu City as a World Heritage site in 2019. World History Encyclopedia notes that 'jade' is a loose term, and that early Chinese distinguished many kinds of stone.

• World History Encyclopedia says the meaning and significance of the cong and bi are still debated. One theory holds that the cong stood for earth and the bi for heaven, but it is not universally accepted.
• At Yaoshan, another Liangzhu site, excavators found 678 jade artefacts, including cong and yue axe blades.
• Fanshan and Jiangjiashan cemeteries together produced 4,229 jade artefacts.

On The Gem Tray: Jade: nephrite vs jadeite, and how to buy real jade

Sources: UNESCO World Heritage: Archaeological Ruins of Liangzhu City (listing 1592); World History Encyclopedia: Liangzhu Culture Jade; Wikipedia: Archaeological ruins of Liangzhu City

Egyptian faience, the ancient stand-in for turquoise and lapis (before 3000 BC to the Late Bronze Age)

Egyptian faience is not the tin-glazed pottery Europeans call faience. It is a sintered-quartz ceramic: crushed quartz or sand, fired until the surface fuses into a glassy blue or blue-green coating, which the Egyptians called tjehenet, 'the gleaming' or 'the dazzling'. World History Encyclopedia says the Egyptians are thought to have perfected it to imitate turquoise and other hard-to-find stones, and Wikipedia notes glazed beads in Predynastic graves at Naqada and other sites. At Serabit el-Khadim, Petrie found the Hathor temple full of glazed votive ware, 'many hundredweights' of fragments, and reckoned that only about a third of what had been broken survived. The Uluburun ship carried some 70,000 glass and faience beads.

• World History Encyclopedia describes the blue hippopotamus nicknamed 'William', now in the Metropolitan Museum of Art, as one of the most famous faience pieces.
• Petrie found glazed wands, menat counterweights, sistra and tablets with the head of Hathor at Serabit, objects left as offerings to the goddess.
• Faience is not clay-based: Wikipedia says it contains the major constituents of glass, silica and lime, and no clay until late periods.

On The Gem Tray: Turquoise: how to tell real from fake, and what looks like it

Sources: W. M. Flinders Petrie, Researches in Sinai (1906), chapter X, the altars and the offerings (Internet Archive); World History Encyclopedia: Egyptian Faience; World History Encyclopedia: Uluburun Shipwreck; Wikipedia: Egyptian faience

Queen Puabi and her headdress (c. 2600 to 2550 BC)

Puabi was a woman of very high rank in the Sumerian city of Ur, about 2550 BC. Her cylinder seal reads 'Pu-abi Nin', and 'nin' can mean lady, queen or priestess. Leonard Woolley dug her tomb, PG 800, between 1922 and 1934 for the British Museum and the Penn Museum. He called her Queen Shub-ad, a reading of the signs that was later corrected. She is known today mainly for what she wore.

How they rose: On her head were three wreaths worn together, according to Woolley's catalogue: gold 'beech-leaf' pendants tipped with carnelian rings on lapis and carnelian beads, gold willow-shaped leaves tipped with carnelian with gold rosettes inlaid with lapis and white paste, and gold ring pendants. Behind them rose a gold comb with seven points ending in gold rosettes with lapis centres, and a gold hair-ribbon lay beneath. Woolley noted that the leaves look like beech, a tree not native to Mesopotamia, and that they have never been identified with certainty.

How they died: Puabi was about 40 when she died. Her physical remains, including pieces of her badly damaged skull, are kept at the Natural History Museum in London, and the finds were divided between the British Museum, the Penn Museum and the Iraq Museum. Woolley's catalogue gives Penn Museum numbers for the wreaths and comb. Her chamber held three personal attendants, and a pit above it held 21 more, though it is unclear whether those were directly linked to her.

• Woolley's name for her, Shub-ad, is still used in older books and in World History Encyclopedia, which gives it as her other name.
• The Great Death Pit at Ur, PG 1237, is a different grave. In it Woolley found six armed guards and 68 serving women, some with gold and silver ribbons in their hair.
• Her seal names no king or husband, which Wikipedia says may indicate she ruled in her own right. Her status is somewhat disputed, since 'nin' can mean lady, queen or priestess.

On The Gem Tray: Famous lapis lazuli artifacts, from the Royal Cemetery of Ur to Tutankhamun

Sources: Woolley, Ur Excavations II: The Royal Cemetery (1934), catalogue of PG 800 (Internet Archive scan); World History Encyclopedia: Ur; GIA Gem Encyclopedia: Lapis lazuli; Wikipedia: Puabi

Indus carnelian and the etched bead (c. 2600 to 1800 BC)

Carnelian is red-orange chalcedony. In the third millennium BC the cities of the Indus Valley turned it into long barrel-shaped beads, some more than five inches long, and into beads with white patterns etched in. Mackay's account, quoted by Woolley, describes coating the carnelian with carbonate of soda, heating it on red-hot iron, and painting the parts meant to stay red with an iron-oxide cement. The beads travelled to Ur, Kish, Susa and as far as the Greek island of Aegina, and archaeologists use them as a marker of trade. J. M. Kenoyer thinks some of the long beads at Ur were made in the Indus Valley and others in Mesopotamia with Indus technology.

• A long carnelian bead in Indus style, found at Susa, carries a dedication to the goddess Ningal by King Shulgi of Ur, according to the Louvre notice quoted on Wikipedia, so a Mesopotamian king's inscription ended up on an Indus-style bead.
• The Indus people also made long terracotta beads painted red to imitate carnelian. Worn as a belt or necklace, Kenoyer notes, they struck against one another with a delicate clinking sound, not unlike the real carnelian beads.
• John Marshall, in his Mohenjo-daro volume, noted that similar long carnelian beads found at Kish had been dated to the pre-Sargonic period, and that he thought beads of this type were made in India and exported to Mesopotamia.

On The Gem Tray: Carnelian: how the stone is treated and dyed, and how to spot the real thing

Sources: Woolley, Ur Excavations II: The Royal Cemetery (1934), quoting Mackay on the bleaching method (Internet Archive scan); Harappa.com: Carnelian Beads, quoting J. M. Kenoyer, Ancient Cities of the Indus Valley Civilization, and John Marshall, Mohenjo-daro; World History Encyclopedia: Indus Valley Civilization; Wikipedia: Etched carnelian bead

Priam's Treasure (Troy II, Early Bronze Age; found 1873)

In 1873, on the mound of Hisarlik in northwest Turkey, Heinrich Schliemann found a cache of gold, silver and copper objects, including two diadems he called the Jewels of Helen, rings, bracelets, cups and a silver vase. He named it Priam's Treasure and wrote that it came from beside the palace of King Priam. The layer was Troy II, an Early Bronze Age city. Priam, if he existed, would have ruled in Troy VI or VII, which World History Encyclopedia puts about a thousand years later.

How it was made and found: Frank Calvert, a British diplomat whose family owned part of the mound, had dug there first and guided Schliemann to it; World History Encyclopedia notes that Schliemann failed to give him credit. Wilhelm Dörpfeld, who joined Schliemann in 1882, corrected the identification of Troy II as Homeric Troy and considered that Troy VI or VII was where the legendary city lay. Schliemann's account of how he found the treasure is unreliable: he wrote that his wife Sophia helped him pack the pieces in her shawl, and later admitted she was in Athens at the time.

Where it is now: Schliemann smuggled the treasure out of the Ottoman Empire, and the Turkish government brought a lawsuit against him in 1876; part went to the Istanbul museum and the rest to Berlin in 1881. After the Second World War it was taken to Moscow, and Russian authorities confirmed in 1993 that they held it (The Art Newspaper), though Wikipedia dates the Pushkin Museum's admission to 1994. Western curators were first allowed to see it in November 1994, and Wikipedia says the objects are likely a composite of several finds rather than the single hoard Schliemann described.

• When Berlin curators were allowed to see the gold in November 1994, it did not appear to have been polished or thoroughly cleaned since its discovery, and about a quarter of the items still seemed to retain traces of the red earth of Troy.
• David Traill's 1984 re-examination in the Journal of Hellenic Studies argued that Schliemann's archaeological reports are distorted by the same tendency to invent and embellish that W. M. Calder III had found in his autobiographical writings.
• In his own book Schliemann wrote that he cut the treasure out with a large knife while his workmen were on a break, at real risk from the wall above him.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: Heinrich Schliemann, Troy and Its Remains (1875), Project Gutenberg; Traill, Schliemann's discovery of 'Priam's treasure': a re-examination of the evidence, Journal of Hellenic Studies 104 (1984); The Art Newspaper: Archaeologists delighted as Schliemann's Trojan treasure becomes available for research (1 December 1994); World History Encyclopedia: Discovery of Troy; Wikipedia: Priam's Treasure

The turquoise mines of Serabit el-Khadim (from c. 1950 BC)

Serabit el-Khadim is a sandstone plateau in southwest Sinai where Egyptian parties mined turquoise and copper and built a temple to Hathor, whom they called mistress of turquoise. Wikipedia says the temple was founded in the Middle Kingdom under Senusret I and partly rebuilt in the New Kingdom, and that the mines were worked by prisoners of war from southwest Asia. Petrie's expedition of 1904 to 1905 found that turquoise lies just beneath an iron-rich bed in the sandstone. Bedouin searched the purple-brown bands, crushed the rock, and rubbed the hard nodules down to see whether they had a turquoise centre. Petrie's team also found short texts in a previously unknown script, now called Proto-Sinaitic, which Wikipedia dates to the beginning of the 16th century BC.

• Petrie's camp numbered thirty-four people, the largest number to have lived and worked in the region since the old Egyptian mining expeditions, as he wrote in his preface.
• GIA notes that the traditional source of the finest turquoise colour is not Sinai but the Nishapur district of Iran, which is why top-colour stone is still called 'Persian blue'.
• Petrie wrote that turquoise is a hydrous phosphate of alumina stained with phosphates of iron (blue) and copper (green) in mixed proportions.

On The Gem Tray: Turquoise: how to tell real from fake, and where it is mined

Sources: W. M. Flinders Petrie, Researches in Sinai (1906) (Internet Archive); GIA: Turquoise description; World History Encyclopedia: Egyptian Faience, on faience as a turquoise substitute; Wikipedia: Serabit el-Khadim

The Mold gold cape (c. 1900 to 1600 BC)

The Mold cape is a Bronze Age shoulder cape of beaten gold, found in 1833 near Mold in Flintshire, Wales. It is covered in embossed ribs and bosses that copy strings of beads. It would fit a slender man or woman, it is heavy, and it makes the upper arms hard to move, so it was probably worn on special occasions.

How it was made and found: It was made from about 700 grams of gold beaten flat and shaped round, then decorated with a punching tool that pushed the metal out from behind. Small holes along the top and bottom meant it could be sewn to an undergarment, and it was probably lined with leather. The gold may be Irish, but the style points to Britain. The beads it copies may be jet: a necklace of nearly 1,000 jet beads was found in another Mold burial mound in the 1950s.

Where it is now: Workmen found it on 11 October 1833 in a mound called Bryn yr Ellyllon, the Hill of the Goblins, while taking the mound apart for road stone, and the gold was crushed and wrapped around a skeleton with amber beads and strips of bronze. The vicar of Mold, Charles Butler Gough, recorded what was found, and the tenant of the field sold his three large pieces to the British Museum in 1836. Professor Terence Powell concluded in 1954 that it was a cape, a 1960s restoration confirmed it, and further work in 2002 completed the shape.

• Experts first thought the pieces were a warrior's corselet, or armour for a pony, and some believed it was made in the AD 400s.
• The finders were workmen from a local workhouse. Of the amber beads found with the cape, only one ever reached the British Museum.
• Some small fragments have since been rediscovered and added back. Others are lost, and some were probably melted down for modern jewelry.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: British Museum on Google Arts & Culture: The Mold Cape; Coflein (Royal Commission on the Ancient and Historical Monuments of Wales): Mold, Bryn-yr-Ellyllon Tumulus, Findspot of Mold Gold Cape; Wikipedia: Mold gold cape

Princess Sithathoriunet's pectoral (c. 1887 to 1878 BC)

Sithathoriunet was a Middle Kingdom princess, presumed to be a daughter of Senusret II, who lived under three kings. Her only trace is her tomb beside his pyramid at El Lahun. Her pectoral, a chest ornament, is cloisonne work: tiny gold cells filled with 372 cut stones. The Metropolitan Museum lists gold, carnelian, lapis lazuli, turquoise and garnet, and gives its size as just 4.5 centimetres high and 8.2 wide. It spells out the throne name of Senusret II, with falcons for the sun god, zigzag lines for the primordial waters, and the god Heh kneeling under the king's name.

How it was made and found: Royal women's jewelry was believed to give magical power that supported the king, which is why his name appears instead of hers. The inscription wishes that the sun god may grant life and dominion over all the sun encircles to Senusret II. The Met's record dates the pectoral to about 1887 to 1878 BC; another museum text gives about 1897 to 1878 BC for the reign.

Where it is now: Ancient robbers plundered her tomb but missed a small recess, which later floods filled with mud that protected the chests inside. Flinders Petrie's team cleared it in early 1914. Gaston Maspero took a few pieces for the Cairo museum, and the Metropolitan Museum of Art bought most of the rest in 1916; the war delayed shipment, and the jewels reached New York in 1919.

• The treasure includes a wig adorned with 1,251 gold rings of two sizes, and a second near-identical pectoral naming Amenemhat III.
• Other items in the recess were a mirror with an inlaid handle, razors and whetstones, a silver dish, calcite oil jars and obsidian cosmetic jars, and scarab rings.
• Her tomb is the main surviving record of her existence. Scholars only presume she was Senusret II's daughter.

On The Gem Tray: Lapis lazuli in ancient Egypt: the stones set in royal jewelry like this

Sources: Metropolitan Museum of Art open-access record: Pectoral and Necklace of Sithathoryunet with the Name of Senwosret II (16.1.3a, b); Egypt Museum: Pectoral and necklace of Princess Sithathoriunet; Wikipedia: Treasure of El Lahun

The Malia bee pendant (c. 1800 to 1700 BC)

The Malia pendant is a gold ornament in the form of two insects with open wings, facing each other, joined at the head and stinger. The Heraklion Archaeological Museum says they hold a disc, probably a honeycomb, and that the round object in their mouths is thought to be a drop of honey. The museum calls it a masterpiece of Minoan miniature art. Malia was one of the four principal Minoan palace sites; World History Encyclopedia lists them in order of size as Knossos, Phaistos, Malia and Zakros.

How it was made and found: It was found in 1930 by French archaeologists in the cemetery of Chrysolakkos at Malia, on Crete, and was first described by Pierre Demargne. The museum says it was made with four techniques: filigree, granulation, repousse and incised decoration. The back is a flat sheet of gold, and a tiny cage on the insects' heads holds a loose bead. The museum reads the gold and the quality of the work as evidence of the prosperity of the ruling class in the era of the First Palaces.

Where it is now: The pendant is on show in the Heraklion Archaeological Museum on Crete. Scholars disagree about the insects. One paper argues they are not bees but belong to the wider order Hymenoptera, and another suggests the goldsmith modelled them on the mammoth wasp Regiscolia maculata. Wikipedia adds that Minoan art often distorts forms for effect.

• The pendant is 4.6 centimetres high and 4.4 centimetres wide.
• The Heraklion museum says honey and wax were important in the Minoan economy, as shown by other finds and laboratory analysis of organic residues.
• Bees also seem to have been symbols of fertility and rebirth in Minoan belief, according to the museum.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: Heraklion Archaeological Museum: Gold bee pendant; World History Encyclopedia: Minoan Civilization; Wikipedia: Malia Pendant

The Nebra sky disc (made c. 1800 to 1700 BC; buried c. 1600 BC; found 1999)

The Nebra disc is a bronze plate about 30 centimetres across, weighing 2.2 kilograms, with a blue-green patina and gold symbols: a disc read as the sun or full moon, a crescent, and stars including a cluster of seven often read as the Pleiades. Wikipedia notes that two golden arcs along the sides are thought to mark the angle between the solstices, and an arc at the bottom is usually read as a solar boat. UNESCO put it on its Memory of the World Register in 2013, calling it 'one of the most important archaeological finds of the twentieth century'. Hyperallergic quotes UNESCO as saying it 'features the oldest concrete depiction of cosmic phenomena worldwide'.

How it was made and found: A 2024 study found the disc was made from a flat cast that was hot forged, with the metal reheated about ten times. The bronze has about 2.6 percent tin. The paper's introduction says associated finds date the burial of the hoard to the end of the central European Early Bronze Age, around 1600 BC, and that the disc itself was highly likely made some 100 to 200 years earlier. Earlier tests linked the copper to Austria and the gold to the Carpathians, and a later analysis traced the first-phase gold, and the tin, to Cornwall, according to Wikipedia.

Where it is now: Henry Westphal and Mario Renner found it in 1999 on the Mittelberg hill near Nebra, using a metal detector without a licence, and sold the hoard the next day for 31,000 Deutsche Marks to a dealer in Cologne. In February 2002 the state archaeologist Harald Meller acquired it in a police-led sting operation in Basel. It is held by the State Museum of Prehistory in Halle. In 2020 Rupert Gebhard and Rudiger Krause proposed an Iron Age date; Ernst Pernicka and colleagues rejected that, and Wikipedia says scientific analyses have confirmed the Early Bronze Age dating.

• The disc was buried with two swords, two axe heads, a chisel and two armbands.
• The looters received sentences of four and ten months from a Naumburg court in September 2003; on appeal, the court raised them to six and twelve months.
• The Halle museum's interpretation, quoted by Hyperallergic, is that a ship making a night journey across the 'celestial ocean' appears here for the first time in Europe as a central mythic symbol. Others have read the same arc as a rainbow, the Aurora Borealis, a comet or a sickle.

On The Gem Tray: Bronze: the alloy that named an age, lost-wax casting and patina

Sources: Dieck et al., Archaeometallurgical investigation of the Nebra Sky Disc, Scientific Reports 14 (2024); Hyperallergic: The First Known Depiction of the Cosmos Adorns a 3,600-Year-Old Disk; Wikipedia: Nebra sky disc

The Mask of Agamemnon (16th century BC; found 1876)

In November 1876 Heinrich Schliemann opened the shaft graves of Grave Circle A inside the citadel of Mycenae, in Greece, and found gold in quantity: World History Encyclopedia says over 15 kilograms of gold objects came from the shaft graves. Eight men were buried in Grave Circle A, and five of them wore masks, in Graves IV and V. The best known, from Grave V, became 'the Mask of Agamemnon'. Wikipedia says modern research dates it to around the 16th century BC.

How it was made and found: Wikipedia says the mask was made from a single thick gold sheet, heated and hammered against a wooden background, with details chased on later. Schliemann's own telegram to King George of Greece, dated 16 (28) November 1876 and printed in his book, says he had found the tombs that tradition, as reported by Pausanias, ascribed to Agamemnon, Cassandra and their companions, surrounded by a double circle of slabs. The popular line that he 'gazed upon the face of Agamemnon' is not in that telegram. Wikipedia says he is 'supposed to have' sent it, so treat the line as a legend.

Where it is now: The mask is in the National Archaeological Museum in Athens. Wikipedia says that close to the end of his life Schliemann accepted doubts about the identification and is quoted as saying, 'let's call him Schulze'. William Calder III and David Traill have also questioned the mask's authenticity, citing its style: it is three-dimensional rather than flat, and alone among Mycenaean face depictions it has a full pointed beard. Defenders note the Greek Archaeological Society sent an ephor, Panagiotis Stamatakis, to watch the dig, and Wikipedia says modern research suggests the mask is genuine but earlier than the Trojan War.

• In his telegram Schliemann said he was working for love of science and gave the treasures to Greece, intact.
• Schliemann took the find as evidence that the Trojan War was a real historical event. Wikipedia says the mask dates 300 to 400 years before the period of the legendary war.
• The Archaeological Society of Athens began excavating at Mycenae in 1841, and Schliemann famously continued the work in 1876, according to World History Encyclopedia.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: Heinrich Schliemann, Mycenae: a narrative of researches and discoveries at Mycenae and Tiryns (1878), Project Gutenberg; UNESCO World Heritage: Archaeological Sites of Mycenae and Tiryns (listing 941); World History Encyclopedia: Mycenae; Wikipedia: Mask of Agamemnon

Baltic amber reaches the Mediterranean (from at least the 16th century BC)

Amber is fossilised tree sap, and the Baltic coast has long been its main source. Wikipedia says amber was moved from northern Europe to the Mediterranean from at least the 16th century BC, and World History Encyclopedia reports that tests on amber from the Mycenaean shaft graves show it largely came from the Baltic. Large Baltic beads are in the breast ornament of Tutankhamun. Pliny the Elder, in the first century AD, reports that Pytheas described an island called Abalus where amber was thrown up by the waves each spring, burned as fuel by the islanders and sold to their neighbours the Teutones. In Roman times a main route ran from the Baltic coast through Poland and the land of the Boii to Aquileia on the Adriatic.

• Pliny reports that amber could be dyed: it was stained with kid-suet and alkanet root, and by his day sometimes dyed purple.
• The Royal Hypogeum of Qatna in Syria holds a quantity of amber unparalleled among known second-millennium BC sites in the Levant and ancient Near East, according to Wikipedia.
• Amber from Sicily was traded earlier: Wikipedia says the oldest amber trade started from Sicily, and that Baltic amber gradually replaced Sicilian amber on the Iberian Peninsula from around 1000 BC.

On The Gem Tray: The gem guides on The Gem Tray, from carnelian to zircon

Sources: Pliny the Elder, Natural History 37.11 and 37.12, on amber (Bostock and Riley translation, Perseus Digital Library); 37.11 gives Pytheas on Abalus, 37.12 the dyeing of amber; World History Encyclopedia: Amber in Antiquity; GIA: Amber description; Wikipedia: Amber Road

Tutankhamun's pectoral with the desert-glass scarab (c. 1332 to 1323 BC; found 1922 to 1925)

Howard Carter's catalogue lists this object as number 267d, a 'lunar and solar breast ornament'. It stands about 14.9 centimetres high. A scarab beetle combined with a solar hawk supports the lunar barque containing the eye of Horus, the crescent in gold and the lunar disc in silver. On the disc the king stands between the gods Ra-Horakhty and Thoth. It is now in the Egyptian Museum in Cairo as JE 61884.

How it was made and found: The scarab is carved from Libyan Desert glass, a natural glass found in the eastern Sahara, in the deserts of eastern Libya and western Egypt. Wikipedia says it formed about 29 million years ago, and that its origin is uncertain: recent research links it to impact features, while some geologists propose an airburst. The Egypt Museum page also quotes a guidebook calling the scarab green chalcedony, so the identification is not always stated plainly.

Where it is now: The ornament came from the tomb of Tutankhamun, KV62, and is in the Egyptian Museum in Cairo (JE 61884). Carter's card for it, number 267d, refers readers to a separate note A for the materials used.

• Carter's card describes the design in detail and refers readers to a separate note for the materials. It gives the height as 14.9 centimetres and the width as 14.5.
• Wikipedia says zircon from the glass shows a structure that forms only when reidite melts at very high temperatures and converts back to zircon. Reidite has been found only at meteorite impact sites, and Wikipedia states that airbursts never produce this mineral transformation.
• According to the Egypt Museum, the pectoral is built in cloisonne technique, inlaid with semiprecious stones and coloured glass, around a canary-yellow scarab of Libyan Desert glass.

On The Gem Tray: The Gem Museum: famous gems and jewels in photos, with the Tutankhamun pectoral

Sources: Griffith Institute, Tutankhamun: Anatomy of an Excavation, Carter No. 267d, card 267d-1; Egypt Museum: Winged scarab pendant of Tutankhamun; Wikipedia: Libyan desert glass

The gold mask of Tutankhamun (c. 1323 BC; found 1925)

The mask covered the head and shoulders of Tutankhamun's mummy. Carter's card gives it as 54.0 centimetres high and 39.3 wide. Eyes and eyebrows are inlaid with lapis lazuli and opaque white calcite, with obsidian pupils and red at the corners of the eyes. Nicholas Reeves calls it perhaps the best-known object from ancient Egypt.

How it was made and found: It is made from two layers of gold between 1.5 and 3 millimetres thick and weighs 10.23 kilograms. X-ray work in 2007 found it is primarily 23 karat gold alloyed with copper, with a very thin surface layer of a paler 18.4 karat gold on the face and neck and 22.5 karat gold elsewhere. Since 2001 some Egyptologists, notably Nicholas Reeves, have suggested it was first intended for Neferneferuaten; the conservator Christian Eckmann, who restored it in 2015, says there are no signs of that.

Where it is now: Carter's team opened the innermost coffin and saw the mask on 28 October 1925. It is now at the Grand Egyptian Museum. In August 2014 the 2.5-kilogram plaited beard came off while the mask was being cleaned, and museum workers fixed it with quick-drying epoxy, leaving it off-centre. A German-Egyptian team reattached it in 2015 using beeswax, and in January 2016 eight museum employees were reported to have been fined and to face discipline.

• The beard had already separated from the mask when it was found in 1925; it was reattached to the chin with a wooden dowel in 1944.
• The 2015 repair used beeswax, a natural material that Wikipedia says the ancient Egyptians also used.
• Carter's card notes that the face has pierced ears, which were afterwards covered over with gold foil.

On The Gem Tray: Gold jewelry: karats explained and what to buy

Sources: Griffith Institute, Tutankhamun: Anatomy of an Excavation, Carter No. 256a, card 256a-1; World History Encyclopedia: Tutankhamun; GIA: Lapis lazuli, history and lore; Wikipedia: Mask of Tutankhamun

The Uluburun shipwreck (sank c. 1320 BC; found 1982)

The Uluburun wreck lies off the southwest coast of Turkey, near Kas, on a slope 44 to 52 metres deep, with artifacts down to 61 metres. Wikipedia gives the sinking as 1320 plus or minus 15 BC, in the late 14th century BC, and says it could not have sunk before the time of Nefertiti because of a gold scarab bearing her name found aboard. World History Encyclopedia estimates the ship at about 15 metres long, built of Lebanese cedar, and says it carried 24 stone anchors. The origins of the objects aboard range from northern Europe to Africa, and as far west as Sicily.

How it was made and found: A sponge diver, Mehmed Cakir, found the wreck in 1982, and the Institute of Nautical Archaeology excavated it from 1984 to 1994, under George Bass in the first season and then Cemal Pulak. The cargo included 348 copper ingots weighing about 10 tons and 120 tin ingots weighing over a ton, which together make bronze. There were also glass ingots in dark blue, turquoise, purple and yellow, perhaps over 175 in all and about 350 kilograms, which World History Encyclopedia says were probably meant for beads or inlay as cheaper substitutes for lapis, turquoise, amethyst and amber.

Where it is now: Turkey owns the finds, which are conserved and displayed at the Bodrum Museum of Underwater Archaeology. By 1998, 47 of the mostly complete glass ingots had been conserved. The conservators' paper says much of the ship's contents were possibly destined for a royal patron and may have been a gift from one royal court to another; World History Encyclopedia says the ship was likely on its way to the Greek mainland.

• The ship carried about 70,000 glass and faience beads, and Baltic amber, in addition to the ingots.
• World History Encyclopedia says the excavated artifacts include scrap gold and silver jewellery, probably carried to be used as payments.
• Many of the tin ingots had been cut into four pieces, which suggests they had been traded before they were loaded, according to World History Encyclopedia.

On The Gem Tray: Bronze: the alloy that named an age, lost-wax casting and patina

Sources: Anastassiades and Ellis, The Conservation of Glass Ingots from the Bronze Age Uluburun Shipwreck, Studies in Conservation 53 (2008); World History Encyclopedia: Uluburun Shipwreck; The Archaeologist: The Discovery of the Uluburun Shipwreck; Wikipedia: Uluburun shipwreck

The High Priest's Breastplate (Exodus 28) (Text of uncertain date; still debated)

Exodus 28 gives instructions for a square breastplate of woven cloth, a span each way and folded double. It carries twelve stones in four rows of three, each in a gold setting and each engraved with the name of one of the twelve tribes of Israel, like a seal. The list of stone names has been translated many ways. The King James version gives sardius, topaz, carbuncle, emerald, sapphire, diamond and so on, but those English names reflect translators' guesses.

How it was made and found: The breastplate is known from the biblical text, whose date of composition is itself debated. Later Greek translations and Josephus offer their own equivalents for the Hebrew names, and these do not always agree.

Where it is now: No breastplate survives, and none has been identified in the archaeological record. What remains is the text, a long tradition of commentary and the unresolved question of what the stones were.

• The Jewish Encyclopedia notes that even the order of the tribal names on the stones is uncertain: rabbinic sources give several arrangements, including the tribes' marching order in the wilderness.
• Wikipedia's survey says some common English identifications are doubtful: rubies were unknown in biblical times, and the Greek topazios of the classical era usually meant peridot, not topaz. The Hebrew sappir probably referred to lapis lazuli.
• The Hebrew name yahalom is the most disputed; a few scholars have proposed diamond. A 2024 study by Ayil claims to identify 11 of the 12 names with a high degree of certainty, with yahalom the exception, which shows the question is still open.

On The Gem Tray: Lapis lazuli: scholars think the Bible's 'sapphire' was this stone, and what to look for today

Sources: Exodus 28:15-21, King James Version (BibleGateway); Jewish Encyclopedia: Breastplate of the High Priest; Wikipedia: Priestly breastplate (Hoshen)

Lydian Electrum and the Gold of Croesus (c. 600 to 546 BC)

Among the first coins ever struck were lumps of electrum, the natural gold-silver alloy found in the river silts near the Lydian capital, Sardis. They carried stamped designs such as a lion and an ox, but their gold content varied. Herodotus says the Lydians were the first people known to him to strike coins of gold and silver. Under King Croesus the kingdom issued coins of nearly pure gold.

How it was made and found: World History Encyclopedia suggests the first electrum coins date perhaps to the reign of Alyattes, father of Croesus, and dates Croesus's reign to 561 to 546 BC. A refinery excavated at Sardis shows how his gold was made: heated with salt at roughly 600 to 800 degrees Celsius to drive off the silver, which gave coins of a guaranteed gold content.

Where it is now: Croesus lost Sardis to Cyrus the Great of Persia around 546 BC (some scholars give 547), and his own fate is disputed (see facts). Croesid coins stayed in use under Persian rule until Darius the Great replaced them with the daric.

• Herodotus (1.94) presents the Lydians as the first to coin gold and silver, and also as the first retail traders. He gives this as what he knows, and modern historians still debate which early issues came first.
• Early Lydian coins were irregular lumps, and electrum varies naturally in how much gold it holds, so a coin's metal could not be trusted to match its face. Refining out the silver is what allowed a coin to carry a known gold content.
• Ancient writers disagree about what happened to Croesus after the fall of Sardis. Herodotus has him condemned to a pyre and saved by rain; Xenophon and others have Cyrus keep him as an adviser; Ctesias makes him a governor of a Median city.

On The Gem Tray: Gold: karats and purity explained, from 24K down to 10K

Sources: Herodotus, Histories 1.94 (Godley translation, Perseus Digital Library); World History Encyclopedia: Gold in Antiquity; World History Encyclopedia: Lydia; Wikipedia: Croesus

The Oxus Treasure (6th to 4th century BC; found about 1877 to 1880)

The Oxus Treasure is a group of about 180 surviving gold and silver pieces and around 200 coins from the Achaemenid Persian period. The metalwork dates from roughly the 6th to the 4th century BC. It includes griffin-headed bracelets in the court style of the 5th and 4th centuries BC.

How it was made and found: It came to light by the Oxus river around 1877 to 1880. The exact findspot is unclear and is often placed near Kobadiyan. Alexander Cunningham, then Director General of the Archaeological Survey of India, wrote in 1881 that it was found in 1877 on the north bank of the Oxus near Takht-i-Kuwat and that most of it had been brought to India for sale. Cunningham himself bought a number of pieces from the dealers.

Where it is now: Augustus Wollaston Franks bought Cunningham's collection and bequeathed all his objects to the British Museum at his death in 1897. The museum holds nearly all the surviving metalwork and shows it in Room 52. In 2007 Tajikistan's president was reported as calling for its return; the museum has kept it, and replicas went to Tajikistan's national museum under a 2013 agreement.

• Early reports suggest about 1,500 coins were originally found, and many pieces were probably melted down before the rest reached collectors. What survives is only part of the find.
• The findspot was near, perhaps some three miles south of, Takht-i Sangin, where Soviet archaeologists later dug an important temple. It is tempting to connect the two, but the link is unproven.
• Some coins linked to the treasure are later than the metalwork, the latest dating to the reigns of Antiochus the Great and Euthydemus I of Bactria, around 200 BC. World History Encyclopedia says the coins may have been added to the group later from another find, so the link is uncertain.

On The Gem Tray: Gold: karats explained, and the oldest large gold treasure yet found

Sources: A. Cunningham, 'Relics from Ancient Persia in Gold, Silver and Copper', Journal of the Asiatic Society of Bengal (1881; Internet Archive); World History Encyclopedia: Oxus Treasure; Wikipedia: Oxus Treasure

Theophrastus and On Stones (Late 4th century BC (the book); died c. 287 BC)

Theophrastus of Eresos, on Lesbos, led the Lyceum in Athens after Aristotle. His short book On Stones (Peri lithon) is a very early surviving Greek treatise on minerals and gems. It classifies stones by their behaviour when heated, and it covers marbles, ores, pigments and materials for glassmaking alongside gems. Later writers, including Pliny, drew on it.

How they rose: He succeeded Aristotle as head of the Lyceum and wrote widely on plants and nature. On Stones comes from that natural-history programme and is more systematic and less fabulous than Pliny's later work, though it still repeats some legends.

How they died: Theophrastus lived from about 372 to about 287 BC, though Caley and Richards note the exact dates are not certain. On Stones was first printed in Greek by Aldus Manutius at Venice in 1497, and the standard modern edition with English translation is Caley and Richards (1956).

• He notes that some stones have the power of attraction: the lyngourion, amber and the lodestone (his 'Heraclean stone'). Amber and lyngourion draw light objects such as straws and bits of wood, while the lodestone draws iron. A later claim that he recorded pyroelectricity, an electric charge from heating, is a misreading: he describes attraction only.
• He records the legend of lyngourion (lyngurium), a stone said to form from the urine of the lynx, and says it attracts straws and bits of wood like amber, a claim some of his sources repeated. Even a careful ancient naturalist passed on fabulous stories.
• He knew that pearls come from shellfish: he calls the pearl a stone made in an oyster, as large as a big fish eye, from India and islands in the Red Sea. His text also mentions the copper mines of Cyprus, where the green stone smaragdos was dug, and an Athenian from the silver mines who found how to prepare cinnabar.

On The Gem Tray: Lapis lazuli: the gold-flecked blue 'sapphire' of the ancient writers

Sources: Theophrastus, On Stones, Greek text with English translation by Caley and Richards (1956; Internet Archive); Wikipedia: On Stones; Mineralogical Record, Schuh's Annotated Bio-Bibliography: Theophrastus

The Arthashastra: A State Handbook for Gems and Mines (Traditionally 3rd century BC; final form by about AD 300)

The Arthashastra, attributed to Kautilya, is a manual of government. Book II, chapter 11 is titled 'Examination of Gems that are to be entered into the Treasury'. It names the regions diamonds come from, says they come from mines, streams and other places, and describes the best stones as large, heavy, hard, regular and brilliant. Elsewhere the state goldsmith must know the kinds, colour, weight and make-up of diamonds, gems, pearls and coral, and the toll on such goods is set by experts.

• Scholars disagree about its date. The traditional dating is the 3rd century BC, but Wikipedia's summary of modern work says the surviving text was probably completed between the 1st and 3rd centuries AD, from earlier treatises.
• A manuscript surfaced in 1905, and the librarian R. Shamasastry published the first English translation in 1915. Before that, colonial-era scholars thought the text lost.
• Among the marks of a good diamond, the text lists that it can scratch vessels. GIA notes that historians think India was trading diamonds by the 4th century BC, and that its supply served only the very wealthy.

On The Gem Tray: Diamond: the stone, hardness and what to check before you buy

Sources: Arthashastra, Book II, translated by R. Shamasastry (Wikisource); GIA: Diamond History and Lore; Wikipedia: Arthashastra

The Roman Gold Ring and Who Could Wear It (Republic to Justinian)

Pliny (Natural History 33.4 to 33.32) tells how Rome's gold ring began as a rare honour. In the Republic the right to wear one belonged to senators, magistrates and equites, and most people wore iron. The emperors controlled it and gave it to individuals, including freedmen. In the end the privilege was extended so widely that it meant little.

• Pliny says a triumphing general had only an iron ring on his finger even while an Etruscan gold crown was held over his head, and that Marius, who triumphed over Jugurtha that way, is said not to have taken a gold ring until his third consulship.
• Smith's Dictionary says Augustus gave the right to a freedman named Mena and to his physician Antonius Musa. In AD 22 Tiberius limited gold rings to free-born men whose father and grandfather held 400,000 sesterces.
• That rule did not hold. Severus and Aurelian gave the ring to all soldiers, and Justinian finally let every citizen wear one.

On The Gem Tray: Gold: karats and alloys, and what a gold ring is really made of

Sources: Pliny the Elder, Natural History 33.4-33.9, the origin of gold rings (Bostock and Riley translation, Perseus Digital Library); Smith's Dictionary of Greek and Roman Antiquities (1875): Annulus (LacusCurtius); Livius.org: Eques; Wikipedia: Equites

The Panagyurishte Treasure (c. 300 BC; found 8 December 1949)

The Panagyurishte Treasure is a set of nine gold vessels: a phiale (shallow bowl), an amphora-rhyton, four animal-head rhyta and three jugs shaped like women's heads. Together they weigh about 6.1 kg (6,164 grams in the 1955 report), and Wikipedia describes the gold as 24-karat, although other sources say 23. They date to the turn of the 4th and 3rd centuries BC. At its discovery it was called the richest treasure found in Europe since the Second World War.

How it was made and found: The brothers Pavel, Petko and Michail Deikov found it on 8 December 1949 while working at the Merul tile factory near Panagyurishte. Peter Gorbanov, a local museum curator, identified it as Thracian.

Where it is now: The original is the centrepiece of the Thracian collection at the Plovdiv museum, and the vessels are also shown in Sofia and Panagyurishte. Replica sets are shown when the original travels abroad.

• The phiale carries an ancient weight, 196 drachmai and a quarter obol, engraved near the rim. On the Attic standard that is within 1.4 grams of the bowl's present weight, according to the 1955 report by Dimiter Tsonchev.
• Experts disagree about who made the set and what it was for. Wikipedia says it is thought to be a royal ceremonial set of the Thracian king Seuthes III, while a Bulgarian museum account speaks of an unknown ruler of the Odrysian tribe and notes ritual-use and Lampsacus-workshop theories. That it was buried to hide it from Celtic or Macedonian invaders is only a theory.
• When the vessels were first announced to the public, they were described as vessels from which Alexander the Great may have drunk, a headline claim from the Illustrated London News of 1954. That was press excitement, not a settled conclusion; the treasure is dated to about the turn of the 4th to 3rd century BC.

On The Gem Tray: Gold: karats, purity and what '24 karat' means

Sources: Dimiter Tsonchev, 'The Gold Treasure of Panagurishte', Archaeology 8 (1955), reproduced as a course reading (Indiana University Pressbooks); BTA (Bulgarian News Agency): The Unearthing of the Panagyurishte Treasure (via Armenpress); World History Encyclopedia: Gold Phiale from the Panagyurishte Treasure (museum photo and caption); Wikipedia: Panagyurishte Treasure

Liu Sheng's Jade Burial Suit (113 BC; found 1968)

Liu Sheng, Prince of Zhongshan, died in 113 BC. His tomb at Mancheng, in Hebei, is described by Wikipedia as the first undisturbed Western Han tomb found. In it, he and his wife Dou Wan, who died about 104 BC, were each sealed in a suit of small jade plaques. The Han belief was that jade could keep a body from decay.

How it was made and found: Liu Sheng's suit is about 1.88 m long and is made of 2,498 jade tablets sewn together with about 1,100 grams of gold wire, according to GIA's Gems & Gemology. GIA calls it the earliest and best-preserved jade burial suit found by archaeologists. The University of Washington's China site adds that it has 12 sections and was estimated to take about ten years to make.

Where it is now: Soldiers digging an air-raid shelter broke into the tomb in 1968, according to National Geographic; Wikipedia credits the archaeologist Wang Zhongshu with the discovery. The suit is now in the Hebei Museum in Shijiazhuang, and Dou Wan's smaller suit was found in the neighbouring tomb.

• World History Encyclopedia says jade was believed indestructible and able to give its owner a kind of immortality, which is why jade objects were so often buried with the dead.
• Counts differ. GIA and the University of Washington give 2,498 plates for Liu Sheng's suit, while World History Encyclopedia says only 'over 1,000' small squares for the couple's suits and Wikipedia says over 2,000 pieces per suit. The gold wire is given as about 1,100 grams (GIA) or two and a half pounds (University of Washington), which is nearly the same weight.
• Dou Wan was buried in her own, smaller suit in a separate tomb nearby. Liu Sheng's suit is 12 sections fitted to the body: face, head, front and back of the tunic, arms, gloves, leggings and feet.

On The Gem Tray: Jade: nephrite vs jadeite, and how to tell real jade

Sources: University of Washington, China Civilization site: Liu Sheng's Jades (museum object notes); Wang and Shi, 'The Evolution of Chinese Jade Carving Craftsmanship', Gems & Gemology, Spring 2020 (GIA; photos from Hebei Museum); National Geographic: These exquisite jade burial suits were just a rumor (2025); World History Encyclopedia: Jade in Ancient China; Wikipedia: Liu Sheng, Prince of Zhongshan

Cleopatra's Pearl (a Story from Pliny) (Set in the 30s BC; written down in AD 77)

The tale comes from Pliny the Elder's Natural History (9.119 to 121), written about a century after the events. In it, Cleopatra owned two enormous pearls. To win a wager with Mark Antony over who could spend more on a single meal, she dropped one of them into a vessel of vinegar and swallowed it once it had dissolved. Pliny tells it as a story about extravagance, so treat it as a tale, not a documented event.

• In Pliny's telling the judge of the bet was Lucius Plancus (Lucius Munatius Plancus), who put his hand on the second pearl just as she was about to dissolve it too, and declared that Antony had lost.
• Pliny says the surviving pearl was cut in two and made into pendants for the ears of a statue of Venus in the Pantheon at Rome. That is his report, and nothing else in the sources confirms it.
• Pearls were old news by then: GIA says a Chinese historian recorded the oldest written mention of natural pearls in 2206 BC.

On The Gem Tray: The Gem Museum: crowns and jewels set with pearls and gems, in photos

Sources: Pliny the Elder, Natural History 9.119-121 (book 9, ch. 58; Bostock and Riley translation, Perseus Digital Library); GIA: Pearl History and Lore; Wikipedia: The Banquet of Cleopatra

Las Médulas, the Roman Gold Mine in Spain (Conquered 25 BC; large-scale mining from the later 1st century AD, about 250 years in all)

Las Médulas, near Ponferrada in León, is one of the largest Roman gold mines in the empire. The Romans undermined the mountain and washed it away with water brought by aqueduct, a method the Romans called ruina montium, 'the wrecking of the mountains', and Pliny describes. UNESCO made the site a World Heritage Site in 1997.

How it was made and found: Northwest Spain was conquered in 25 BC under Augustus, and large-scale production began in the second half of the 1st century AD. Pliny (33.70 to 78) describes mining in Spain in general, not Las Medulas by name: galleries propped with timber, mountains brought down, and water channelled from far off to wash the debris.

Where it is now: Wikipedia gives the working life of the district as about 250 years. Pliny reports that, according to some authorities, Asturia, Gallaecia and Lusitania together yielded 20,000 Roman pounds of gold a year, mostly from Asturia; Wikipedia converts this to about 6,560 kg.

• Pliny says miners split hard rock by fire and vinegar, then cut away the wooden props so that the mountain broke apart and fell with a crash he calls impossible to imagine, while a sentinel on a peak signalled the workers to flee.
• Wikipedia notes that the aqueducts that brought the water were also used to wash the alluvial gold deposits.
• World History Encyclopedia notes that traces of this Roman mining technology still survive at Las Médulas.

On The Gem Tray: Gold: karats and alloys, and how to tell real gold from plated

Sources: Pliny the Elder, Natural History 33.66-78, mining in Spain (Bostock and Riley translation, book 33 ch. 21, Perseus Digital Library); World History Encyclopedia: Roman Engineering; Wikipedia: Las Médulas

The Periplus and the Roman Trade with India (1st century AD)

The Periplus of the Erythraean Sea is an anonymous Greek merchant's handbook to the Red Sea, East Africa, Arabia and India. At the Malabar ports of Muziris and Nelcynda it lists exports that include transparent stones of all kinds, diamonds, sapphires and fine pearls, though pepper was the main cargo. The author seems to have made the voyage himself.

• Section 56 of the Periplus lists 'diamonds and sapphires' among exports from the Muziris and Nelcynda region. Those are the translator's English words for Greek names, and the ancient names do not always match modern gem species.
• A Tamil poem, the Akananuru, describes Yavana (western) ships arriving with gold and leaving with pepper. World History Encyclopedia says black pepper made up about three-quarters of the bulk of western cargo at Muziris.
• Scholars do not agree on the book's date. The text says 40 to 55 AD on one reading, and its translator Wilfred Schoff preferred about 60 AD.

On The Gem Tray: Where gems are mined: an interactive map of where each gem comes from

Sources: The Periplus of the Erythraean Sea, Schoff translation (1912; Wikisource); World History Encyclopedia: Periplus of the Erythraean Sea; World History Encyclopedia: The Eastern Trade Network of Ancient Rome

Pliny the Elder and Book 37 (Natural History finished AD 77; Pliny died AD 79)

Gaius Plinius Secundus was a Roman officer and writer whose 37-book Natural History ends with the gems. In Book 37 he calls the diamond the most valuable of all human possessions, says only kings and a very few others knew it, and passes on tales like cutting it with goat's blood. He also records that Nero watched gladiators through an emerald.

How they rose: He was born in AD 23 or 24 at Novum Comum (Como) and finished the Natural History in AD 77, dedicating it to the future emperor Titus.

How they died: He died at Stabiae in AD 79 (traditionally 25 August) during the eruption of Vesuvius, while attempting to rescue people. Wikipedia notes that in 1859 Jacob Bigelow concluded from the nephew's letter that he had died of apoplexy or heart disease.

• Book 37 (section 64) says the emperor Nero watched gladiator fights through an emerald. The Latin reads 'in smaragdo'.
• Pliny says diamonds are so hard that they resist hammer blows, and that the anvil may split. He then claims that fresh, warm goat's blood can break one. That claim is a myth, and diamonds were not cut this way. The Bostock and Riley notes say it may have been a dealers' story to hide the real method.
• GIA notes that Pliny praised emerald as the greenest of stones: nothing greens greener.

On The Gem Tray: Emerald: lab vs natural, why emeralds are oiled, and what to buy

Sources: Pliny the Elder, Natural History, Book 37 (Bostock and Riley translation: diamond ch. 15, emerald ch. 16; Perseus Digital Library); GIA: Diamond History and Lore; GIA: Emerald History and Lore; Wikipedia: Pliny the Elder

The Hoxne Hoard (Buried after AD 407; found 16 November 1992)

The Hoxne Hoard holds 14,865 Roman coins, with 569 gold solidi, plus about 200 items of silver tableware and gold jewellery. The jewellery comprises 29 gold pieces, among them a body chain, six necklaces, three rings and nineteen bracelets. The latest coins date the deposit to after AD 407, probably around 408. Counts differ slightly between records: Suffolk's Historic Environment Record, an older tally, lists 565 gold solidi.

How it was made and found: Eric Lawes, a retired gardener and amateur detectorist, found it on 16 November 1992 in a field near Hoxne while looking for a hammer the tenant farmer Peter Whatling had lost. He stopped digging and reported it, so the Suffolk Archaeological Unit could excavate the deposit the next day, which the British Museum says greatly improved what is known about it.

Where it is now: A coroner declared it treasure on 3 September 1993, and the Treasure Trove Reviewing Committee valued it at 1.75 million pounds, which Lawes shared with Whatling. The British Museum acquired it in April 1994, and its best pieces are in Room 49.

• The 'Empress' pepper pot is a hollow silver bust of a woman, one of four pepper pots in the hoard. The British Museum notes that such pepper containers (piperatoria) are very rare finds, from a time when pepper was imported from India.
• One gold bracelet is inscribed VTERE FELIX DOMINA IVLIANE, a good-luck wish to a 'Lady Juliane'. It is the only inscription on the gold items.
• Why it was buried is unknown. World History Encyclopedia lists several ideas: a votive deposit, loot hidden by a thief, or, as the simplest explanation, a wealthy family hiding its wealth after AD 407 as Roman troops left Britain. Some common items are missing from it, so it may be only part of a larger treasure.

On The Gem Tray: Gold: how to read purity and tell real gold from plated

Sources: Suffolk Heritage Explorer: Monument record HXN 019, The Hoxne Hoard (Suffolk County Council Historic Environment Record); Google Arts & Culture / British Museum: How a Metal Detector Discovered Roman Treasure; World History Encyclopedia: The Roman Hoxne Hoard; Smithsonian Magazine: A Search for a Lost Hammer Led to the Largest Cache of Roman Treasure Ever Found in Britain; Wikipedia: Hoxne Hoard

Sutton Hoo (Buried about 610 to 635; excavated 1939)

Sutton Hoo is a pair of Anglo-Saxon cemeteries near Woodbridge on the River Deben. Mound 1 held an undisturbed ship burial with gold and garnet work on the sword pommel and belt, the shoulder clasps, the great gold buckle and a purse-lid. The purse-lid carried seven plaques of gold, cloisonne garnets and millefiori glass. Coins in the grave date the burial to about 610 to 635.

How it was made and found: The landowner Edith Pretty hired the self-taught archaeologist Basil Brown. He started on the mounds in June 1938 and in May 1939 found iron ship rivets in Mound 1. On 14 June 1939 he reached the burial chamber, which earlier robbers had dug into but missed. Pretty then handed the dig to Charles Phillips of Cambridge.

Where it is now: A treasure trove inquest held in the autumn of 1939 decided the treasure belonged to Pretty as landowner, and she gave it to the nation. Most objects are now in the British Museum. When war began in September 1939 the finds were stored in a disused London Underground tunnel.

• The National Trust counts 263 finds from the 1939 dig, including a pattern-welded sword and fragments of the helmet.
• Rædwald, the first king of the East Angles who is known as a real historical figure, is the favoured candidate for the burial, an idea put forward by H. M. Chadwick in 1940. The identification is still debated; Eorpwald, who died in 627 or 628, also fits the coin dates.
• The purse hung from the belt holding 37 gold Frankish coins, each from a different mint, plus three blank coins and two small ingots. Its leather pouch rotted away in the ground; only the gold frame and catch of the lid survive, with their garnet and glass plaques.

On The Gem Tray: Garnet: the red stone of Anglo-Saxon cloisonne, and how to buy it today

Sources: National Trust: Basil Brown, Edith Pretty and the 1939 Sutton Hoo dig; World History Encyclopedia: The Sutton Hoo Purse-lid (British Museum object); Wikipedia: Sutton Hoo

The Staffordshire Hoard (Buried about 650 to 675; found 5 July 2009)

The Staffordshire Hoard is the largest hoard of Anglo-Saxon gold found. It holds about 5.09 kg of gold and 1.44 kg of silver in almost 4,600 items and fragments, with over 3,500 cut garnets. About a third of the fragments come from a single high-status helmet.

How it was made and found: Terry Herbert, a metal detectorist, found it on 5 July 2009 near Hammerwich in Staffordshire, and it was announced on 24 September 2009. The objects were made in the 6th and 7th centuries and were probably deposited between 650 and 675.

Where it is now: The Treasure Valuation Committee set the price at 3.285 million pounds in November 2009. Birmingham Museum and Art Gallery and the Potteries Museum in Stoke-on-Trent bought it jointly in 2010, helped by a 1.285 million pound grant from the National Heritage Memorial Fund.

• Birmingham Museums says the small garnets came from the Czech Republic and the larger cut ones from the Indian subcontinent.
• How the garnets were cut is still an open question, according to the museum's research team.
• Birmingham Museums says the designs show links to many regions of Europe, and that about a third of the fragments belong to one helmet, of which a replica is displayed.

On The Gem Tray: Garnet: the red stone of the Sutton Hoo clasps, and its many varieties

Sources: Birmingham Museums: The Science behind the Staffordshire Hoard; Birmingham Museum & Art Gallery: Staffordshire Hoard; Wikipedia: Staffordshire Hoard

The Muisca Raft and El Dorado (Made c. 1200 to 1500 (dating debated); found 1969)

The Muisca raft is a votive piece of gold work from Colombia, 19.5 cm long, 10.1 cm wide and 10.2 cm high. It shows a large central figure, read as the chief, with ten smaller figures around him, eleven in all. The Banco de la Republica reads it as the investiture ceremony of the chief of Guatavita, the ceremony behind the El Dorado story. Spanish writers described that ceremony as a chief covered in gold dust and rowed out on a lake.

How it was made and found: It was cast in one piece by the lost-wax method. The Banco de la Republica says its date probably falls in the late Muisca period: its summary box gives 600 to 1600 AD and its text gives 1200 to 1500. A radiocarbon test on casting charcoal, reported by Wikipedia, gave 1295 to 1410.

Where it is now: A farmer, Cruz Maria Dimate, found it in 1969 in a ceramic jar in a cave in the paramo of Pasca, and the bank bought it that April. It is in the Museo del Oro in Bogota.

• Wikipedia gives a radiocarbon date from casting charcoal of 1295 to 1410 and an alloy of about 65 percent gold. The bank's entry says over 80 percent gold. The sources disagree.
• It was not found at Lake Guatavita. Wikipedia says other anthropologists and historians think the raft does not refer specifically to the Guatavita ceremony, since similar ceremonies were recorded across Muisca territory. An earlier raft from the Siecha lagoon, found in 1856, was lost.
• World History Encyclopedia says the El Dorado story appears in most Spanish conquest accounts, including Fernandez de Oviedo's (1535 to 1548), and that Spanish attempts in the 1580s to drain Lake Guatavita failed when a landslide blocked the cut.

On The Gem Tray: Gold: alloys with silver and copper, and what karats mean

Sources: Enciclopedia Banrepcultural: Balsa muisca (Museo del Oro record O00015); World History Encyclopedia: El Dorado, the Gilded Ruler of Ancient Colombia; Wikipedia: Muisca raft

Marco Polo on the Balas Rubies and Ceylon (Travels dictated about 1298; Polo died 1324)

In his Travels, Polo says the province of Badashan produced the 'Balas rubies' from one mountain, dug only on the king's account. Anyone else who dug there risked forfeiting life and goods. In the chapter on Ceylon he describes a ruby, held by its king, about a palm long and as thick as a man's arm, which he calls the finest and biggest in the world.

How they rose: Polo was born in 1254 and served Kublai Khan from about 1275 to 1292. His account was recorded from dictation by his fellow prisoner Rustichello of Pisa, and it circulated around 1298. The book itself says it mixes what Polo saw with what others told him.

How they died: Polo died in 1324, aged about 70. Henry Yule's notes to his translation record that the balas ruby is like the spinel and takes its name from Badakhshan.

• Polo says the Badashan king sold only a few stones so that the market would not be flooded and the Balas would keep its value.
• Polo claims that rubies are found in Ceylon and in no other country. Yule's own notes mention the rubies of Ava, so the claim does not hold.
• Polo says the Great Khan offered the ransom of a city for the Ceylon ruby, and that the king refused. Hayton, quoted in Yule's notes, adds that the ruby was placed in the new king's hand at his coronation.

On The Gem Tray: Spinel: the 'balas ruby' of the old kings, and how to buy it today

Sources: Marco Polo, The Travels, Yule-Cordier edition, vol. 1 (Badashan; Project Gutenberg #10636); Marco Polo, The Travels, Yule-Cordier edition, vol. 2 (Ceylon; Project Gutenberg #12410); GIA: Spinel History and Lore; World History Encyclopedia: Marco Polo

Mandeville's Growing Diamonds (Written between 1357 and 1371)

The Travels of Sir John Mandeville was a hugely popular travel book. Its chapter on diamonds says they grow on crystal rocks in the cold north of India, grow together as male and female, and are nourished by the dew of heaven. It adds that a diamond worn on the left side gives courage, victory in a rightful cause and protection from enchantment.

• The narrator claims he has often tested this himself: kept with a little rock and wet with May dew, a diamond will grow every year. That is a story, not an observation.
• Wikipedia says the author was probably not a real 'Sir John Mandeville', and that the book borrows heavily, for example from Odoric of Pordenone for its travels in the Far East.
• The book was extremely popular and was translated into many languages. Wikipedia says Columbus was heavily influenced by it and by Marco Polo.

On The Gem Tray: Diamond: how natural diamonds really form, and what to check before you buy

Sources: The Travels of Sir John Mandeville, ch. XVII (Project Gutenberg #782); GIA: Diamond History and Lore; Wikipedia: The Travels of Sir John Mandeville

The Black Prince's Ruby (1367 to today)

The Black Prince's Ruby is a large, irregular, cabochon red spinel of 170 carats, about 4.3 cm long. Spinels were not told apart from rubies until 1783, so the stone was called a balas ruby. It is set at the front of the Imperial State Crown, above the Cullinan II diamond.

How it was found: GIA says the stone was probably mined in Afghanistan and first appears in 14th-century Spanish records. GIA and tradition say Edward, Prince of Wales, the Black Prince, received it in 1367 as payment for help given to Peter of Castile, but Wikipedia notes that this account is a legend that dates from the 1760s. The story that Pedro took the stone from a Granadan prince is not well verified, and the claim that Henry V wore it at Agincourt in 1415 is flagged in Wikipedia as lacking a citation.

Where it is now: Henry VIII's 1521 inventory lists a 'great balas ruby' in the Tudor Crown, thought to be this stone. After the Commonwealth sold the royal gems, a large 'ruby' was bought for the Crown Jewels in 1661 for 400 pounds, which may have been this one. The Imperial State Crown was made for Queen Victoria's coronation in 1838, with the spinel at the front, and remade in 1937. The stone is set in that crown, shown in the Tower of London.

• GIA describes balas rubies as large spinel crystals from ancient mines in central and southeast Asia, treasured by kings and often changed hands as spoils of war.
• The crown made for Queen Victoria in 1838 carried 3,093 gems, and a small plaque on the back of the spinel commemorates the crown's history. The stone is polished but not faceted, a smooth cabochon with an irregular outline.
• GIA says the stone survived fires, an attempted theft and the bombing of the Second World War.

On The Gem Tray: Spinel: the red stone mistaken for ruby for centuries

Sources: GIA: Spinel History and Lore; Wikipedia: Black Prince's Ruby

Columbus's Pearls and the Cubagua Fisheries (1498 to 1541)

In 1498 Columbus reached the coast of Paria and wrote to the Spanish crown that many natives wore pieces of gold on their breasts, some with bracelets of pearls. He sent boats ashore to get some and named a body of water the Gulf of Pearls. From 1499 Spanish expeditions harvested pearl oysters intensively at Cubagua.

• Columbus says he did not pursue the pearls because his food was running out, his eyes were weak and his large ship was unsuited to the task.
• Wikipedia reports that the Spanish enslaved local people for diving and then brought Lucayan divers from the Bahamas. It estimates as many as 40,000 were taken by 1513.
• Wikipedia says the pearl beds were being depleted badly by 1531, and the Spaniards limited production. By 1539 fewer than 50 people remained on Cubagua, and an earthquake and tsunami destroyed the city of Nueva Cadiz in 1541.

On The Gem Tray: The Gem Museum: crowns and jewels set with pearls and gems, in photos

Sources: Select Letters of Christopher Columbus, Hakluyt Society (Project Gutenberg #77820); GIA: Pearl History and Lore; Wikipedia: Cubagua

Montezuma's Gold, Seen by Dürer (1519 to 1521)

In his Second Letter, Hernán Cortés told Charles V that Montezuma and his lords gave gold in bars and sheets, gold and silver jewels, featherwork and stones, which he assigned to the Emperor and valued at 100,000 ducats and more. He says Montezuma had everything on land and in the sea copied in gold, silver, stones and feathers. The painter Albrecht Dürer, who saw Aztec objects that had been shipped to Charles V, wrote that he had never seen anything that moved his heart so much.

How it was made and found: The Met's essay says Montezuma sent gifts to Cortés, among them a gold disk the size of a cartwheel and a silver one, and that Cortés sent them to Spain, where they were shown to the new emperor Charles V in the spring of 1520. Durer, travelling in the Netherlands, saw objects brought to the King from 'the new land of gold' in Brussels: a sun all of gold a fathom broad and a silver moon of the same size, with armour and weapons. He valued the lot at 100,000 gulden. The Met gives the date as August 1521, but his journey began in 1520, and most accounts place his visit in the summer of 1520.

Where it is now: The Met says none of the works from that shipment is known to survive: the gold and silver pieces were melted down and the feathers and other perishable objects were thrown away. The gold Cortes gathered later in Tenochtitlan was a separate pile. Cortes says all the gold and jewels his men carried were lost in the flight from the city on the night of 30 June 1520, and World History Encyclopedia says he lost about eight tons of loot.

• Dürer's diary says he had never seen anything that moved his heart so much, and admired 'the subtle ingenuity of men in foreign lands'.
• Cortés says the pieces were so marvellous that for their novelty and strangeness they had no price.
• World History Encyclopedia says that when Cortés met the Aztec ruler in November 1519 he was given a necklace of golden crabs.

On The Gem Tray: Gold: karats explained, and how gold is alloyed with silver and copper

Sources: Letters of Cortes to Charles V, Second Letter, 30 October 1520 (MacNutt translation; Wikisource); Albrecht Durer, Records of Journeys to Venice and the Low Countries (Tombo translation; Project Gutenberg #3226); Metropolitan Museum of Art, Heilbrunn Timeline: Gold of the Indies (Julie Jones, 2002); World History Encyclopedia: The Gold of the Conquistadors; World History Encyclopedia: The Fall of Tenochtitlan

The Koh-i-Noor in Babur's Memoirs (First reliable record 1526; recut 1852)

After the battle of Panipat in 1526, the family of the slain Raja of Gwalior offered Humayun a mass of jewels. Babur's memoir says it included a famous diamond that every appraiser valued at two and a half days' food for the whole world, and that it weighed 8 miskals. Babur says Humayun offered it to him and he gave it back.

How it was found: Babur, founder of the Mughal empire, wrote the account in his memoirs, which Annette Beveridge translated in 1922. Her editorial note identifies it with the Koh-i-Noor. World History Encyclopedia says some historians think Babur described a different stone.

Where it is now: Nader Shah took the diamond to Persia in 1739, Ranjit Singh got it in 1813, and the Treaty of Lahore of 1849 gave it to Queen Victoria. Recut in 1852 at Prince Albert's direction, it fell from 186 to 105.6 carats and is now in the Queen Mother's crown at the Tower of London.

• Translations of Babur's value differ: Beveridge's English reads two and a half days' food for the world, while other versions, quoted by GIA and World History Encyclopedia, give half the world's daily expense.
• The recut took 38 days, and Wikipedia says the stone's original cut had drawn criticism at the Great Exhibition of 1851.
• The curse is a legend: Wikipedia says the rumour may have started in the Delhi Gazette and spread through the Illustrated London News, and one version held that only male rulers were affected.

On The Gem Tray: History of gem faceting: from Mughal-style cuts like the Koh-i-Noor's to the modern brilliant

Sources: The Babur-nama in English (Beveridge), Project Gutenberg #44608; GIA 4Cs: Famous Diamonds, The Koh-I-Noor; World History Encyclopedia: Koh-i-Noor; Wikipedia: Koh-i-Noor

Cellini's Gold Salt Cellar (the Saliera) (1540 to 1543; stolen 2003, recovered 2006)

The Saliera is a table piece of gold, enamel, ebony and ivory, 26.3 cm high, made 1540 to 1543 for King Francis I of France. Wikipedia says the gold was hammered by hand, not cast. The Kunsthistorisches Museum calls it the only extant work in gold by the Florentine, and reads its design as an allegory of the cosmos, with Neptune for the sea and Tellus for the earth.

How it was made and found: In his Autobiography, Cellini says that in Rome he made a model for a salt cellar for the Cardinal of Ferrara. In Paris he then showed the same wax model to the King, who asked for it in gold. Cellini says he asked a thousand crowns of gold and the King ordered the money paid that day.

Where it is now: Charles IX of France gave it to Archduke Ferdinand II of Tyrol, and it moved from Castle Ambras to the museum in Vienna in the 19th century. It was stolen on 11 May 2003 and found on 21 January 2006, buried in a lead box in a forest near Zwettl. The thief, Robert Mang, was sentenced to four years.

• Wikipedia says alarms on the night of the theft were dismissed as false, and the loss went unnoticed until the morning.
• The museum offered a reward of one million euros. Robert Mang gave himself up after police released surveillance photos that acquaintances recognised, according to Wikipedia.
• The Autobiography, which Cellini wrote around 1558, is the source for the commission, and World History Encyclopedia calls it colourful, so it should be read as one man's telling. In it he says that when he first showed Francis I the model, the Cardinal of Ferrara recognised it as the one Cellini had made for him in Rome.

On The Gem Tray: Jewelry making: the tools and metals goldsmiths still use

Sources: Kunsthistorisches Museum: Saliera (object record); The Autobiography of Benvenuto Cellini, Symonds translation (Project Gutenberg #4028); World History Encyclopedia: Benvenuto Cellini; Wikipedia: Cellini Salt Cellar

Potosi and the Silver Mountain (1545 to 1821)

Cerro Rico at Potosi was the great silver mine of the Spanish empire. World History Encyclopedia says that around 1600 it counted over 600 mines and made about 9 million silver pesos a year, more than all other silver mines in the world together. Spain relied on a forced-labour system, the mita.

• Sources disagree on the discovery. World History Encyclopedia and Wikipedia credit Diego de Huallpa in 1545. The chronicler Pedro de Cieza de Leon, who saw it in 1549, says a Spaniard named Villaroel found the veins and that the hill was first worked in 1546.
• Cieza says every Saturday the metal was melted down at the house of the local magistrate, and the royal fifth came to more than 120,000 castellanos a month.
• The mita was brought back in 1574 by Viceroy Francisco de Toledo, according to Wikipedia, and World History Encyclopedia says it was not abolished until 1821.

On The Gem Tray: Silver: sterling, fine silver and coin silver explained

Sources: Pedro de Cieza de Leon, Travels (Chronicle of Peru), ch. CIX (Markham translation; Project Gutenberg #48770); World History Encyclopedia: The Silver of the Conquistadors; Wikipedia: Cerro Rico

Agricola's De Re Metallica (Published 1556; English translation 1912)

Georgius Agricola (Georg Bauer) wrote De re metallica on mining, refining and smelting. It appeared in 1556, a year after he died, because its 292 woodcuts took longer to finish. Book VII covers assaying and Books IX to XI cover smelting and separating metals, including gold and silver.

• In the assay chapters, gold is rubbed on a touchstone to find how much silver it holds. The line is compared with lines from a needle of known gold or silver content.
• In his preface Agricola answers critics who say mining kills: miners are crushed, fall down shafts and, he reports the critics saying, breathe air that rots their lungs.
• Wikipedia says it stayed the leading mining reference for about 180 years. Herbert Hoover and his wife Lou Henry Hoover made the first English translation in 1912.

On The Gem Tray: How to tell if gold is real: the touchstone and other tests

Sources: Georgius Agricola, De Re Metallica, Hoover translation (Project Gutenberg #38015); Smithsonian Libraries: Georgii Agricolae De re metallica libri XII; Wikipedia: De re metallica

Garcia de Orta on Diamonds (Colloquies published 1563; Orta died 1568)

Garcia de Orta practised medicine in Goa and, Wikipedia says, also traded in spices, drugs and precious stones. His Colloquies on the Simples and Drugs of India (1563) includes a Colloquy on diamonds, written as a dialogue with a Spanish doctor, Ruano. Ruano calls the diamond the king of stones, but Orta replies that lapidaries think more of a perfect emerald or ruby. He names the diamond rocks of Bisnaguer (Vijayanagar) and the Deccan and calls several old claims fables.

How they rose: He was born about 1501 in Castelo de Vide, Portugal, to Spanish Jewish parents who had been forced to convert, and he practised in Goa from 1538 as physician to several successive Portuguese viceroys and governors and to a local sultan, Burhan Nizam Shah of Ahmadnagar.

How they died: He died in Goa in 1568. His sister Catarina was burned at the stake for Judaism in 1569, and in 1580 Garcia himself was convicted after death: his remains were exhumed and burned with an effigy at an auto-da-fe on 4 December 1580.

• Orta says that if you try the hammer test on a diamond of price you will smash the diamond to pieces; he saw lapidaries break a badly shaped large diamond in a metal mortar. He calls the he-goat's blood story a fable and says he tried it himself.
• He rejects the belief that diamond powder is poison, and says he knew of a woman who gave ground diamonds to her sick husband for many days without killing him.
• He reports that the Canarese valued the uncut 'naife' diamond above the cut one, the way a virgin is worth more than a woman who is not one, while the Portuguese valued polished stones most. At the Bisnaguer mines a stone of 30 carats belonged to the king, and the largest he had seen himself was 140 carats.

On The Gem Tray: Diamond: the hardest gem, lab-grown vs mined, and what to check before you buy

Sources: Garcia de Orta, Colloquies on the Simples and Drugs of India, 43rd Colloquy, Diamonds (Markham translation, 1913; Internet Archive); GIA: Diamond History and Lore; Wikipedia: Garcia de Orta

The Golconda diamond mines (16th century to 1687 (mines worked into the 1800s))

Golconda, near today's Hyderabad, was the capital of the Qutb Shahi sultans and the market for the diamond pits of the Krishna River region. GIA counts roughly 20 mines working there between the 16th and the mid-19th century. Until diamonds were found in Brazil in the early 1700s, India was the world's main supplier. Many famous stones, including the Hope and the Koh-i-Noor, are linked to the area, though for most of them the link is likely rather than documented.

• GIA says only about 2 percent of all diamonds are type IIa, a group with no measurable nitrogen or boron, and it ties Golconda stones to that group.
• At the Kollur mine Tavernier found "close upon 60,000 persons" at work on his first visit: men digging, women and children carrying earth.
• Tavernier described a trade test for blue tint in a diamond: carry the stone under a leafy tree and look at it in the green shadow.

On The Gem Tray: Where gems are mined: a world map of the sources, old and new

Sources: Tavernier, Travels in India, vol. 2 (1676; V. Ball translation, 1889), Internet Archive; GIA 4Cs blog: Diamonds on Location, Golconda; GIA (J. Shigley): Historical Reading List, Diamonds in Ancient India; Wikipedia: Golconda Fort

Jean-Baptiste Tavernier (1605 to 1689 (journeys 1630 to 1668))

Tavernier made six journeys to Persia and India between 1630 and 1668, buying and selling gems at courts that Europeans rarely saw. His Six Voyages (Paris, 1676) is the main eyewitness source for the Golconda mines and the Mughal treasury. Historians use it with care, because he wrote from memory and for a European audience.

How they rose: He travelled as a merchant at his own expense and sold stones to the French king, including a large rough blue diamond, in 1668. In 1669 he bought the lordship of Aubonne near Geneva and became Baron of Aubonne.

How they died: He died in Moscow in 1689, aged 84. The story that wild dogs or wolves killed him as punishment for the blue diamond is a myth.

• The Smithsonian says he sold Louis XIV the blue diamond together with 14 other large diamonds and several smaller ones in 1668. GIA counts 20 diamonds in the sale.
• In 1665 he was allowed to weigh the Great Mogul diamond himself and recorded 319 and a half ratis, which he reckoned at about 280 carats.
• Tavernier saw a single peacock over the canopy of the Mughal throne. The court chronicler Lahori, writing earlier, describes two peacocks on top of each of the twelve pillars.

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: Tavernier, Travels in India, vol. 2 (1676; V. Ball translation, 1889), Internet Archive; Smithsonian Institution: History of the Hope Diamond; GIA Gems & Gemology (Fall 2019): Gemstones in the Era of the Taj Mahal and the Mughals; Wikipedia: Jean-Baptiste Tavernier

The Peacock Throne (1635 to 1747)

The Peacock Throne was the Mughal emperors' seat in the Diwan-i-Khas of the Red Fort, named for the peacocks on its canopy. It took about seven years to build and was covered in rubies, emeralds, pearls and diamonds. It stands for the way Mughal rulers used stones as symbols of power.

How it was made and found: Shah Jahan commissioned it, and it was inaugurated in March 1635.

Where it is now: After Nader Shah of Persia defeated the Mughal emperor at Karnal in February 1739 and sacked Delhi, he took the throne as a war prize. It disappeared after his assassination in 1747, most probably broken up for its stones. A later replacement was lost around the 1857 rebellion; its marble base survives.

• Tavernier counted about 108 large balas rubies on it, all cabochons, and about 116 emeralds. He also saw a diamond of 80 to 90 carats hung on the side facing the court.
• Old jewel lists called red spinel "balas ruby", so many of the big "rubies" on the throne were probably spinels.
• Wikipedia gives its cost as about twice that of the Taj Mahal. GIA writes that the throne went to Persia in 1739 and was added to what became Iran's crown jewels.

On The Gem Tray: Spinel: the "balas ruby" of old Mughal jewel lists, and why famous "rubies" like Timur's are spinels

Sources: Tavernier, Travels in India, vol. 1 (1676; V. Ball translation, 1889), Internet Archive; GIA Gems & Gemology (Fall 2019): Gemstones in the Era of the Taj Mahal and the Mughals; Wikipedia: Peacock Throne

The Great Mogul diamond (c. 1650, then lost to the record)

The Great Mogul was a very large Golconda diamond that belonged to the Mughal emperors. It is known almost entirely from Tavernier's account, which includes a drawing. It was the stone Europeans meant when they talked about the greatest diamond in the world.

How it was found: Wikipedia says it was found around 1650, probably near the Kollur mine. In Tavernier's account, Mir Jumla gave it to Shah Jahan about 1656 or 1657 as a rough stone, which Tavernier puts at 900 ratis (787 and a half carats) in one place and 907 ratis (about 794 carats) in another. The Venetian Ortensio Borgio ground it down so heavily that the king fined him 10,000 rupees.

Where it is now: Tavernier saw it in Aurangzeb's treasury in 1665, weighed it himself and recorded 319 and a half ratis, about 280 carats. After Nader Shah's sack of Delhi in 1739 it drops out of the record. Many modern accounts identify it with the Orlov diamond in the Russian imperial sceptre, but that is an inference, not a documented chain of owners.

• Tavernier described its shape as that of an egg cut through the middle, and his book includes a drawing of it.
• He wrote that a European cutter would have cleaved good pieces off the rough stone instead of grinding it, and that Borgio was "badly rewarded" for his work.
• Wikipedia says most modern scholars are convinced the Great Mogul is the Orlov, while the Cape Town Diamond Museum says only that some believe it. The link is an inference from the stone's description, not a documented chain of owners.

On The Gem Tray: How gems are cut: from rough crystal to faceted stone, step by step

Sources: Tavernier, Travels in India, vol. 2 (1676; V. Ball translation, 1889), Internet Archive; GIA Gems & Gemology (Fall 2019): Gemstones in the Era of the Taj Mahal and the Mughals; Cape Town Diamond Museum: Famous Diamonds; Wikipedia: Great Mogul Diamond

The Hope Diamond (1668 to today)

The Hope is a 45.52-carat deep blue diamond in the Smithsonian's National Museum of Natural History. It is almost certainly a recut of the French Blue, which Tavernier sold to Louis XIV. It glows red for several seconds after exposure to short-wave ultraviolet light.

How it was found: Tavernier bought a rough diamond of "beautiful violet" colour in India, 112 3/16 old carats, and sold it to Louis XIV in 1668. In 1673 the court jeweller Jean Pitau recut it to 67 1/8 old carats (about 69 modern carats), the French Blue, which Louis XV had set in a Golden Fleece insignia in 1749.

Where it is now: The French Blue vanished in September 1792, when thieves emptied the royal storehouse. In 1812 a 45.5-carat deep blue diamond is described in London with the dealer Daniel Eliason, and in 1839 it appears in the catalogue of Henry Philip Hope's gems. Evalyn Walsh McLean bought it from Cartier in 1911, Harry Winston bought her collection in 1949, and Winston's firm gave the stone to the Smithsonian on 10 November 1958.

• In 2009 researchers reported a lead cast of the French Blue in a Paris museum. Computer models showed that the Hope could have been cut from it.
• The "Hope curse" is a story, not a record. Wikipedia notes that Tavernier lived to 84 and died of natural causes, and says the curse story may have been fuelled by Cartier around the time of the 1911 sale.
• The Smithsonian classes it as a type IIb diamond and attributes the blue colour to trace boron in the crystal. In 1974, out of its setting, it weighed 45.52 carats, not the 44.5 carats reported for years.

On The Gem Tray: The Gem Museum: the Hope Diamond and other famous stones, in photos

Sources: Tavernier, Travels in India, vol. 2 (1676; V. Ball translation, 1889), Internet Archive; Smithsonian Institution: History of the Hope Diamond; GIA Gems & Gemology (Spring 2009): The French Blue and the Hope, New Data from the Discovery of a Historical Lead Cast; Wikipedia: Hope Diamond

The Regent diamond (1698 to today)

The Regent is a 140.64-carat cushion-shaped brilliant, almost colourless with a trace of blue-green, that belongs to the French state. It was bought for France in 1717 and has been set in the crowns and swords of several rulers. The Louvre says it is still considered the most beautiful diamond in the world for its purity and the quality of its cut.

How it was found: It was found in 1698 in the Golconda mines. Thomas Pitt, governor of Fort St George in Madras, bought the rough stone, which weighed 426 carats, and it reached England in 1702. It was cut there by a jeweller named Harris between 1704 and 1706.

Where it is now: Philippe d'Orleans, regent of France, persuaded the Regency Council to buy it on 6 June 1717. It was stolen in 1792, found hidden in a roof frame in 1793, pledged several times under the Directory and Consulate, and recovered by Napoleon in 1801. It was one of the few pieces the state kept when the other crown jewels were sold in 1887, and it is held by the Louvre.

• A legend says an enslaved miner hid the stone in a leg wound during the 1687 siege of Golconda and was murdered by a sea captain. It is a story, not a record.
• One long-told account says Pitt sent the stone to London hidden in the heel of his son's shoe. Rumours that he had cheated the seller led Alexander Pope to satirise him.
• Napoleon had it set in the hilt of the First Consul's sword in 1801, and in 1812 in the emperor's sword. The Louvre says the cutting also gave several smaller stones, which were sold to Tsar Peter the Great.

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: Musee du Louvre, collections database: Diamant, dit le Regent; GIA Gems & Gemology (Fall 2020, R. Shor): A History of European Royal Jewel Sales; Wikipedia: Regent Diamond

Platinum reaches Europe (1736 to 1786)

Platinum is very dense and would not melt in the furnaces of the time. People in what is now Ecuador had worked it centuries earlier, but Europe did not know it. The Spanish naval officer Antonio de Ulloa described it from the gold sands of Colombia in a book published in 1748, and Charles Wood sent samples from Jamaica to William Brownrigg, whose report reached the Royal Society in 1750. In 1786 Pierre-Francois Chabaneau, backed by Charles III of Spain, produced 23 kg of pure, malleable platinum. It later became a jewellery metal.

• Julius Caesar Scaliger wrote in 1557 of a noble metal found between Darien and Mexico that no fire could liquefy. This is thought to be the first European mention of the metal.
• Ulloa called platina a stone of such resistance that it is hard to break or crush by a blow on a steel anvil. Miners in the Choco sometimes abandoned gold workings because of it.
• Archaeologists link the pre-Columbian platinum-gold work at Esmeraldas, Ecuador, with the La Tolita culture, which they date to roughly 600 BC to AD 200.

On The Gem Tray: Platinum: what 950 means, how it wears, and how it compares with white gold

Sources: Juan and Ulloa, Relacion historica del viage a la America meridional, Part 1 vol. 2 (Madrid, 1748), Internet Archive; Brownrigg and Watson, Several Papers concerning a New Semi-Metal, called Platina, Philosophical Transactions vol. 46 (Royal Society), OCR transcription; Encyclopedia.com (Dictionary of Scientific Biography): Antonio de Ulloa; Wikipedia: Platinum

The Koh-i-Noor (1739 to today (recut in 1852))

The Koh-i-Noor ("Mountain of Light") is a 105.6-carat oval brilliant in the crown made for Queen Elizabeth the Queen Mother in 1937. Its history before the 18th century is uncertain, and India, Pakistan, Iran and Afghanistan have all made claims on it. The British government says it was acquired legally under the Last Treaty of Lahore in 1849.

How it was found: It probably came from the Golconda region of southern India. The record before 1739 is thin, and some scholars think the big diamond in Babur's memoirs was a different stone. Nader Shah took it from Delhi in 1739, and the Persian biographer Muhammad Kazim Marvi is the first writer to call it the Koh-i-Noor.

Where it is now: After Nader Shah's death in 1747 it passed to Ahmad Shah Durrani's line, then to Shah Shuja, and in 1813 to Ranjit Singh of the Punjab. Article III of the terms of 29 March 1849, signed by the boy ruler Duleep Singh, required the stone to be surrendered to the Queen of England. It was presented to Queen Victoria on 3 July 1850, shown at the Great Exhibition in 1851, recut in 1852 at Prince Albert's direction, and is on show at the Tower of London.

• The 1852 recut took the stone from 186 old carats to 105.6 carats and left it with 66 facets. The original cut had 169.
• The idea that it brings bad luck to male owners, so only women should wear it, may have started in a newspaper rumour, possibly in the Delhi Gazette, repeated by the Illustrated London News.
• Only women of the royal family have worn it since it reached Britain. It was set in Queen Alexandra's crown, used at her 1902 coronation, then Queen Mary's crown in 1911 and the Queen Mother's in 1937.

On The Gem Tray: A history of gem faceting, from rose cuts like the old Koh-i-Noor to the modern brilliant

Sources: Aitchison, A Collection of Treaties, Engagements and Sanads, 4th ed., vol. 8 (1909), Internet Archive (Punjab terms of 1849; scan has no text layer); The Conversation (A. Kumar, University of Nottingham): No ordinary diamond, how the Koh-i-Noor became an imperial possession; World History Encyclopedia: Koh-i-Noor; Wikipedia: Koh-i-Noor

The Affair of the Diamond Necklace (1784 to 1786)

The crown jewellers Boehmer and Bassenge made a necklace of about 650 diamonds, possibly for Louis XV's mistress Madame du Barry, and Marie Antoinette refused to buy it. Jeanne de la Motte used forged letters to persuade Cardinal de Rohan that the queen secretly wanted it, and in January 1785 the jewellers handed it to Rohan, who passed it to her; it was broken up and the stones sold, mostly in London. When the first instalment fell due the jewellers went to the queen, and Rohan was arrested at Versailles on 15 August 1785. The Parlement of Paris acquitted him in May 1786, and Jeanne de la Motte was whipped, branded with a V for voleuse and imprisoned. The queen was innocent, but the case badly hurt her reputation.

• The World History Encyclopedia gives the necklace as 647 brilliants weighing about 2,800 carats, priced at around two million livres. Versailles says the asking price was cut to 1.6 million livres, the figure in Rohan's own defence brief.
• To convince Rohan, the plotters staged a midnight meeting in the Grove of Venus at Versailles in which a Paris woman, Nicole d'Oliva, played the queen.
• Jeanne de la Motte escaped from the Salpetriere prison, published her memoirs in London in 1789, and died there in 1791 after falling from a window.

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: Memoire pour Louis-Rene-Edouard de Rohan, accuse (Paris, 1786), legal defence brief, Internet Archive; Chateau de Versailles: The affair of the diamond necklace, 1784-1785; World History Encyclopedia: Affair of the Diamond Necklace; Wikipedia: Affair of the Diamond Necklace

René Just Haüy (1743 to 1822)

Abbé Haüy is called the father of modern crystallography. In 1784 he proposed that a crystal's faces follow simple whole-number rules, built up from tiny identical units. His four-volume Traité de minéralogie (1801) put the method in front of every collector.

How they rose: He was ordained a Catholic priest in 1770. A broken specimen of calcite in a friend's collection drew his attention to the smooth, flat planes along which crystals split, and he built a mathematical theory from them. In 1802 he became professor of mineralogy at the Muséum national d'histoire naturelle.

How they died: He died in Paris on 1 June 1822. His Traité de cristallographie also appeared in 1822 and was long the standard book on the subject.

• Haüy's own account in the 1801 Traité, as quoted by Wikipedia, says he divided a calcite specimen in other directions until he extracted its rhomboid nucleus. Wikipedia adds that, according to some accounts, he dropped it, a detail that comes only from those retellings.
• He refused the oath to the Civil Constitution of the Clergy during the Revolution and was jailed after 10 August 1792. Etienne Geoffroy Saint-Hilaire pleaded for his release.
• Napoleon made him an honorary canon of Notre-Dame on 5 April 1802. Wikipedia says he is styled Abbé Haüy after that honour, though he had been a priest since 1770.

On The Gem Tray: How gems are cut: from rough crystal to faceted stone, step by step

Sources: Haüy, Traité de minéralogie, vol. 1 (Paris, 1801), Internet Archive; Encyclopedia.com: Haüy, Abbé René-Just; Wikipedia: René Just Haüy

The theft of the French Crown Jewels (1792 and 1887)

In September 1792, during the Revolution, thieves broke into the Garde-Meuble, the royal treasury in Paris, and took most of the crown jewels over several nights. Many pieces were recovered, including the Regent, found hidden in a roof frame in 1793. The French Blue was not, and it reappeared in London about twenty years later as a smaller blue diamond. A law of December 1886 authorised the sale of the crown jewels, which ran in nine sessions at the Louvre from 12 to 23 May 1887. The state kept the Regent, the Hortense diamond, Napoleon's crown and a few other pieces, and Tiffany & Co. bought more than two thirds of the lots.

• Most of the Mazarin diamonds were stolen with the rest, and only five were recovered in the weeks after the theft.
• The 1887 sale brought in 7,221,560 francs, of which 6,864,050 francs came from gems and jewellery.
• The Paris jeweller Frederic Boucheron bought the Grand Mazarin diamond and two other Mazarin diamonds for 101,000 francs.

On The Gem Tray: The Gem Museum: the Hope Diamond and other famous stones, in photos

Sources: Musee du Louvre, collections database: Diamant, dit le Regent; GIA Gems & Gemology (Fall 2020, R. Shor): A History of European Royal Jewel Sales; GIA Gems & Gemology (Spring 2009): The French Blue and the Hope, New Data from the Discovery of a Historical Lead Cast; Wikipedia: French Crown Jewels

Mohs' hardness scale (1812 (first proposed) and 1822 to 1824 (full text))

Friedrich Mohs ranked ten reference minerals by which can scratch which, from talc (1) to diamond (10). A mineral's number is the hardest reference mineral it can scratch. The scale is only a ranking: the steps are not equal, and diamond (10) is about four times harder than corundum (9) in absolute terms. Scratch tests were centuries old, and Theophrastus and Pliny both describe them. The Dictionary of Scientific Biography says Mohs first proposed the ten-step scale in his Versuch of 1812, while Scientific American's history blog says the scale was published in his Grund-Riss der Mineralogie of 1822 to 1824.

• Corundum (ruby and sapphire) is rated 9, but diamond is roughly four times harder, so the jump from 9 to 10 is far bigger than the jump from 8 to 9.
• Sources disagree on the date: the Dictionary of Scientific Biography ties the scale to Mohs' 1812 Versuch, and others give the 1822 to 1824 Grund-Riss.
• Mohs studied under Abraham Werner at Freiberg and succeeded him there in 1818. He wrote about "Fossilien", the word then used for any mineral dug from the ground.

On The Gem Tray: Gem hardness chart: Mohs numbers for every common gem, and what they mean for wear

Sources: Mohs, Versuch einer Elementar-Methode zur naturhistorischen Bestimmung und Erkennung der Fossilien, vol. 1 (Vienna, 1812), Internet Archive; Mohs, Grund-Riss der Mineralogie, part 1 (Dresden, 1822), Internet Archive; Encyclopedia.com (Dictionary of Scientific Biography): Friedrich Mohs; Scientific American blog (History of Geology): Mohs scale of hardness; Wikipedia: Mohs scale of mineral hardness

The California Gold Rush (1848 to 1855)

On 24 January 1848 James Marshall found gold in the tailrace of the sawmill he was building for John Sutter at Coloma, on the South Fork of the American River. Marshall later said that he picked it up and it made his heart thump, because he was certain it was gold. The news spread slowly at first, and the merchant and newspaper publisher Samuel Brannan helped spread it from San Francisco and sold supplies to miners. President Polk told Congress about the discovery on 5 December 1848, and the rush of 1849 followed. Historians date the rush from 1848 to 1855, and modern estimates are that as much as 12 million ounces of gold came out in the first five years.

• In his message of 5 December 1848 Polk said that when an army officer visited the district in July, about 4,000 people were collecting gold. He asked for a branch of the U.S. Mint in California.
• The National Park Service estimates that some 140,000 emigrants reached California by the California Trail between 1849 and 1854.
• Sutter's business was ruined when his workers left for the goldfields, and squatters took his land and stole his crops and cattle. More than 20,000 Chinese miners landed in San Francisco in 1852.

On The Gem Tray: Gold jewelry: karats, purity and colours explained

Sources: James K. Polk, Fourth Annual Message to Congress, 5 December 1848 (Miller Center); National Park Service: The California Gold Rush; California State Parks: Marshall Gold Discovery State Historic Park; Wikipedia: California Gold Rush

The Victorian gold rush (1851 to the 1860s)

Gold was found at several sites in Victoria in 1851, and a Gold Discovery Committee in Melbourne later paid rewards to the finders. James Esmond's find at Clunes on 1 July 1851 was the first marketable goldfield, and Thomas Hiscock found gold at Buninyong on 8 August. Ballarat, Mount Alexander and Bendigo followed, and Victoria's output was greater than any other country's except California's for several years. Its best year was 1856, with 3,053,744 troy ounces. At Ballarat the miners' protest against licence fees ended in the Eureka Stockade on 3 December 1854, where at least 24 miners died.

• Melbourne grew from about 29,000 people in 1851 to about 123,000 in 1854.
• The Welcome Nugget, found at Ballarat in 1858 by a party of 22 Cornish miners, weighed 69 kg. It sold in Melbourne for just over 10,000 pounds and was bought by the Royal Mint in London, which melted it into sovereigns.
• William Howitt, writing about Ballarat in 1855, describes shafts of 130 to 160 feet. Sovereign Hill says Ballarat shafts passed 30 metres by 1853.

On The Gem Tray: Gold jewelry: karats, purity and colours explained

Sources: William Howitt, Land, Labour and Gold; or, Two Years in Victoria (1858), Internet Archive; Sovereign Hill: The Story of the Welcome Nugget; Sovereign Hill: Surviving the Ballarat gold rush; Wikipedia: Victorian gold rush

The Comstock Lode (1859 to 1880)

The Comstock Lode, under Mount Davidson in Nevada, was the first major silver discovery in the United States, and Virginia City grew up almost overnight around it. Credit for the discovery is disputed: Wikipedia says the Grosh brothers may have found it in 1857, and in spring 1859 Peter O'Riley and Patrick McLaughlin struck the Ophir ground, where the blue-black material clogging their rocker assayed on 27 June as a rich silver sulphide. Henry Comstock claimed part of the ground, and the lode took his name. Output peaked in 1877, and the bonanza period was over by 1880. Deep mining continued sporadically until 1918, when the last pumps were shut off.

• The USGS estimates that about 7,500 tons of mercury were lost in the Carson River basin during the 20 years of ore processing from 1860 to 1880, because mercury was used to recover the silver and gold.
• Samuel Clemens tried mining on the Comstock before he began writing as Mark Twain for the Territorial Enterprise, and he describes the silver rush in Roughing It.
• Most of the original claim holders sold early. Wikipedia says Patrick McLaughlin sold his one-sixth share of the Ophir claim for $3,000 and soon lost the money, while Peter O'Riley held on and sold for about $40,000.

On The Gem Tray: Silver jewelry: sterling vs fine silver vs plated, why it tarnishes, and what 925 means

Sources: Mark Twain, Roughing It (1872), Project Gutenberg #3177; Bureau of Land Management: The Comstock Lode; US Geological Survey Circular 1170: Carson River mining areas; Wikipedia: Comstock Lode

The Eureka and the Star of South Africa (1867 to 1974 (and on))

The Eureka, found in 1866 or 1867, is generally taken as the first authenticated diamond from South Africa. Two years later a larger stone, the Star of South Africa, followed. The finds on the Orange and Vaal rivers began the diamond rush that led to Kimberley.

How it was found: A 15-year-old, Erasmus Jacobs, found the Eureka near Hopetown on the Orange River. Acting Civil Commissioner Lorenzo Boyes said he believed it was a diamond, and Dr William Guybon Atherstone of Grahamstown confirmed it at 21 1/4 carats. In March 1869 a Griqua shepherd found an 83.5-carat stone, and Schalk van Niekerk bought it for 500 sheep, 10 oxen and a horse.

Where it is now: The Eureka, cut from 21.25 to 10.73 carats, stayed in Britain for about a century. De Beers bought it in 1967 and gave it to the South African people, and it is in the Kimberley Mine Museum. The Star, cut to 47.69 carats and set by the Earl of Dudley in a hair ornament with 95 smaller diamonds, was sold at auction in Geneva on 2 May 1974 for 1.6 million Swiss francs.

• Sources disagree on what the Cape governor, Sir Philip Wodehouse, paid for the Eureka: 500 pounds in Williams and Wikipedia, 1,500 pounds at the Cape Town Diamond Museum.
• In 1946 the Eureka was sold at Christie's in London, set in a bangle, for 5,700 pounds.
• Van Niekerk sold the Star on to the Lilienfeld brothers of Hopetown for 11,200 pounds, and it was later bought for 25,000 pounds by the Earl or Countess of Dudley, depending on the source.

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: Gardner F. Williams, The Diamond Mines of South Africa (1902), Internet Archive; Cape Town Diamond Museum: Famous Diamonds; Kimberley City Info: Today in Kimberley's history, 19 March (the Star of South Africa); Wikipedia: Eureka Diamond

The Kimberley Big Hole (1871 to 1914)

Diamonds were first found in mid-July 1871 at Colesberg Kopje, on the farm Vooruitzigt, and the mine dug there is known as the Big Hole. The diggers' camp grew to about 50,000 people by 1872. The pit was long said to be the largest hand-dug excavation on Earth, though a later review suggests that the hand-dug parts of Jagersfontein may have been larger. De Beers bought the Kimberley Mine in 1889 (see the De Beers entry). Open-pit work stopped on 14 August 1914, after more than 22 million tons of rock had been removed, and De Beers later mined the pipe underground to 1,097 metres.

• The recorded yield is about 2,722 kg of diamonds from 22.5 million tons of earth. Wikipedia gives 2,720 kg (13.6 million carats) and another passage gives 3,000 kg.
• The pit was dug to 240 metres, but debris and water have filled much of it, and about 175 metres is now visible.
• The first diamonds were found at Colesberg Kopje by members of the "Red Cap Party" from Colesberg, according to Wikipedia. The ensuing scramble for claims gave the place the name New Rush.

On The Gem Tray: Where gems are mined: a world map of the sources, old and new

Sources: Gardner F. Williams, The Diamond Mines of South Africa (1902), Internet Archive; Getaway: Unearthing the story behind Kimberley's Big Hole; Wikipedia: Big Hole

The Fabergé Imperial Easter eggs (1885 to 1917)

The Hen Egg of 1885 started a series of jewelled Easter gifts from the House of Fabergé to the Russian imperial family. Alexander III gave one to his wife every year, and Nicholas II kept up the custom for his mother and his wife. The eggs are among the best-known objects in the history of jewellery.

How it was made and found: Alexander III ordered the first egg for Empress Maria Feodorovna. Fabergé was to make a version of an early 18th-century French egg from the Danish royal family, but he made an original variation: an enamelled gold shell with a gold yolk, a gold hen and a tiny diamond crown. The emperor asked for a small egg of a precious stone in place of the ring in the model.

Where it is now: Fifty eggs were delivered between 1885 and 1917, and 44 survive in whole or in part. The Bolsheviks nationalised the House of Fabergé after the Revolution. In 2004 Viktor Vekselberg bought the nine eggs of the Malcolm Forbes collection before they reached auction, and in a 2013 BBC documentary he said he had spent just over 100 million US dollars.

• Wikipedia says the Hen Egg cost 4,151 rubles, and that its diamond crown and ruby pendant surprises have since been lost.
• The Karelian Birch egg was never delivered, and the Blue Tsesarevich Constellation egg was only partly finished when the 1917 revolution came.
• The Hillwood museum's Twelve Monogram Egg of 1896 has the crowned ciphers of Alexander III and Maria Feodorovna set in diamonds on blue enamel. Its surprise is missing.

On The Gem Tray: The Gem Museum: jewelled objects and famous stones, including a Fabergé egg, in photos

Sources: Fabergé Museum, St Petersburg: Hen Easter Egg; Hillwood Estate, Museum and Gardens: Twelve Monogram Egg (collection record); Wikipedia: Fabergé egg

The Tiffany Setting (1886)

In 1886 Charles Lewis Tiffany introduced the Tiffany Setting, which holds one round brilliant diamond high on six prongs so that light reaches it from the sides. Tiffany & Co. says the design was so sought after that the firm had to warn the public about counterfeits. The claim that it was the first ring to lift a diamond off the band is the company's own, not an independently checked fact. The six-prong solitaire is still sold under the Tiffany name and copied widely. GIA links the rise of the diamond engagement ring to the South African discoveries, which put diamonds within reach of the rising middle class.

• At the 1887 sale of the French Crown Jewels in Paris, Tiffany & Co. bought more than two thirds of the lots, according to GIA.
• GIA says the six-prong setting was introduced to bring more light, and so more brilliance and sparkle, to faceted diamonds.
• Tiffany says that at the end of the 19th century rings were heavily embellished, with gemstones set low against the band.

On The Gem Tray: Fine diamonds: what to check when buying a 1 to 3 carat stone

Sources: Tiffany & Co. press site: The Tiffany Setting (the company's own statement); GIA 4Cs blog: Victorian Style Engagement Rings; Sotheby's: The Brilliant History of Tiffany and Co. Jewelry; GIA Gems & Gemology (Fall 2020, R. Shor): A History of European Royal Jewel Sales

The Witwatersrand gold rush (1886 to the 1890s)

The Witwatersrand ("the Rand") is a belt of gold-bearing conglomerate about 50 km long. Jan Bantjes found small reefs in June 1884, and George Harrison's find on the farm Langlaagte in 1886 showed where the main reef lay; South African History Online dates it to July and World History Encyclopedia to February. Harrison is reported to have sold his claim for under 10 pounds. Johannesburg grew to about 100,000 people within a decade, and by 1915 South Africa mined about 40 percent of the world's gold. Mine owners, many of them Kimberley diamond men, backed the failed Jameson Raid of December 1895, and the Second Boer War followed in 1899.

• The first railway line in the Transvaal, from Johannesburg to Boksburg, opened on 17 March 1890.
• The richest early mine owners included Julius Wernher, Barney Barnato, Alfred Beit and Cecil Rhodes, and many of them had made their fortunes at Kimberley.
• Hatch and Chalmers noted in 1895 that the reef is "very pyritic" below the oxidised zone, and the cyanide process was first used on the Rand in 1890.

On The Gem Tray: Gold jewelry: karats, purity and colours explained

Sources: Hatch and Chalmers, The Gold Mines of the Rand (1895), Internet Archive; South African History Online: Discovery of the Gold in 1884; World History Encyclopedia: Witwatersrand Gold and the Creation of South Africa; Wikipedia: Witwatersrand Gold Rush

The MacArthur-Forrest cyanide process (1887 to 1890)

John Stewart MacArthur and the brothers Robert and William Forrest developed the process in 1887 for the Tennant company in Glasgow. Crushed ore is mixed with a dilute cyanide solution, which dissolves the gold and leaves most other metals behind; the gold is recovered from the solution afterwards. That gold dissolves in cyanide had been known since Scheele's experiments in 1783. The British patent was dated 19 October 1887, the US application was filed on 9 November 1887 and the US patent was granted on 14 May 1889. In the 1880s the Rand's deeper ores were pyritic and the older methods could not treat them, so the process, first used on the Rand in 1890, set off an investment boom.

• The US patent's claim is for a cyanide solution with cyanogen in a proportion not exceeding eight parts to one thousand parts of water.
• W. R. Feldtmann reported in 1894 that "cyanide gold" made up 29.9 percent of the Witwatersrand's output in March 1894, up from about 22 percent for the whole of 1893.
• In 1896 Bodlander confirmed that oxygen is needed for gold to dissolve in cyanide, something MacArthur had doubted.

On The Gem Tray: Gold jewelry: karats, purity and why most jewelry gold is an alloy

Sources: US Patent 403,202 (MacArthur and Forrest), Process of Obtaining Gold and Silver from Ores, granted 14 May 1889, Google Patents; W. R. Feldtmann, Notes on gold extraction by means of cyanide of potassium (MacArthur-Forrest patents), Witwatersrand (1894), Internet Archive; South African History Online: Gold, Diamonds and Deep Mines, South Africa's Mineral Revolution; Wikipedia: Gold cyanidation

De Beers Consolidated Mines (1888 to 1889)

By the 1880s the contest at Kimberley was between Cecil Rhodes's De Beers and Barney Barnato's Kimberley Central. De Beers Consolidated Mines was formed on 12 March 1888, and Rhodes then set out to win control of the Kimberley Mine. Rhodes and Alfred Beit bought Kimberley Central shares until Barnato came to terms, and Barnato was paid in De Beers shares. Williams gives 5,338,650 pounds as the price of De Beers' control of the Kimberley Mine, and the deal was done in 1889. Barnato went on to sit for Kimberley in the Cape Parliament from 1889 to 1897.

• When Rhodes asked where the money would come from, Beit answered, "We will get the money if we can only get the shares", as Rhodes told shareholders.
• Williams says Beit furnished most of the money for the share-buying contest, and that taking control would cost at least 2,000,000 pounds.
• South African History Online says Barnato jumped from the ship and drowned on 14 June 1897 on his way to London.

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: Gardner F. Williams, The Diamond Mines of South Africa (1902), Internet Archive; Kimberley City Info: Today in Kimberley's history, 12 March (De Beers Consolidated Mines); South African History Online: Barney Barnato; World History Encyclopedia: Witwatersrand Gold and the Creation of South Africa

Moissan and the meteorite crystals (1893 to 1904)

Henri Moissan was a French chemist who built an electric arc furnace. In 1893 he began studying fragments of the Canyon Diablo meteorite from Arizona and reported microscopic diamonds in it. The crystals that later carried his name were silicon carbide, which he identified in 1904. He also tried to make diamonds by cooling molten iron rapidly, and GIA reports that he believed for the rest of his life that he had succeeded, though modern attempts to repeat the work produced only silicon carbide. Natural moissanite is very rare (the largest known crystal, found in Israel, is 4.1 mm long), and the moissanite sold in jewellery today is lab-grown, first marketed as a gem by Charles & Colvard in 1998.

• Moissanite is birefringent, so it shows double refraction under magnification, which helps a gemmologist tell it from diamond.
• Moissan won the 1906 Nobel Prize in Chemistry for isolating fluorine.
• In Le four electrique (1897) Moissan describes a transparent yellow diamond from the Canyon Diablo meteorite, 0.7 mm by 0.3 mm.

On The Gem Tray: Moissanite: what it is, how it differs from diamond, and who it suits

Sources: Henri Moissan, Le four electrique (Paris, 1897), Internet Archive; GIA (J. Shigley): Historical Reading List, Historical Attempts to Synthesize Diamond; GIA Gems & Gemology (Summer 2014): Record-Size Natural Moissanite Crystals Discovered in Israel; Wikipedia: Moissanite

Kokichi Mikimoto and the cultured pearl (1858 to 1954 (first pearl 1893))

Kokichi Mikimoto was born in Toba on 25 January 1858. He bred akoya oysters in Ago Bay and, after years of failure, produced hemispherical cultured pearls on 11 July 1893. Round cultured pearls came later, and who deserves the credit is argued about.

How they rose: Wikipedia and the New World Encyclopedia say he patented a method for hemispherical pearls (mabe) in 1896 and a mantle-tissue method in 1908. The round pearl method was developed in the same years by Tatsuhei Mise and Tokichi Nishikawa, who both sought Japanese patents in 1907, and GIA says Mikimoto began using the Mise-Nishikawa method in 1916. His US patent 1,328,008, filed on 23 July 1919 and granted on 13 January 1920, describes a process to produce "perfectly spherical pearls".

How they died: Mikimoto died on 21 September 1954, aged 96. The island where he worked, off Toba, is now Mikimoto Pearl Island and a museum in his honour.

• In 1927 Thomas Edison is said to have met him and been amazed by pearls that were supposed to be biologically impossible.
• In 1935, with prices falling, Mikimoto publicly burned tons of low-quality pearls to protect his firm's name.
• According to GIA, Mise implanted 15,000 mollusks in 1902 and harvested small round pearls two years later, and round cultured pearls reached the market in 1921.

On The Gem Tray: The Gem Museum: pearls and other famous gems, in photos

Sources: US Patent 1,328,008 (K. Mikimoto), Process for causing oysters to produce pearls, granted 13 January 1920, Google Patents; GIA 4Cs blog: History of Cultured Pearls, Part 1; nippon.com: Mikimoto Kokichi, the Pearl King and His Museum; New World Encyclopedia: Mikimoto Kokichi; Wikipedia: Kokichi Mikimoto

The Klondike Gold Rush (1896 to 1899)

In August 1896, on Rabbit Creek (soon renamed Bonanza Creek) in the Yukon, a party that included George Carmack, Keish (Skookum Jim Mason), Shaaw Tlaa (Kate Carmack) and Kaa Goox (Dawson Charlie) found gold. The National Park Service notes that there are several versions of who deserves credit. Carmack, the only American in the group, filed the first claim. The news reached the world in July 1897, when the steamers Excelsior and Portland brought gold into San Francisco and Seattle. Gold found near Nome, Alaska, in summer 1899 drew many prospectors away and Dawson City's population fell.

• Canadian rules required every entrant to bring a year's supply of food, typically about 1,150 pounds, so a traveller hauled close to a ton of supplies in relays.
• Harold Goodrich, writing in 1897, explains that miners used fire to thaw frozen ground and sank shafts through it, a method called burning and drifting.
• Gold production in the Klondike peaked in 1903, years after the rush itself, when heavier equipment such as dredges was brought in.

On The Gem Tray: Gold jewelry: karats, purity and colours explained

Sources: H. B. Goodrich, The gold fields of Klondike and the Yukon Valley (Engineering Magazine, Sept. 1897), Internet Archive; National Park Service, Klondike Gold Rush NHP: Gold Discoverers; National Park Service: George Carmack; Wikipedia: Klondike Gold Rush

Verneuil's flame-fusion ruby (1902 to 1911)

Auguste Verneuil, a French chemist, announced in 1902 that he could make rubies by letting powdered alumina fall through an oxyhydrogen flame, and he published his methods in 1904. The molten drops land on a support and grow into a single crystal called a boule. The same method still makes the cheapest synthetic ruby and sapphire. Flame-fusion rubies were probably in circulation a few years before 1902: the so-called Geneva rubies appeared in 1885, and Verneuil had been the assistant of Edmond Fremy, who made rubies in molten alumina baths. His US patent for synthetic blue sapphire, filed on 10 May 1910 and granted on 28 March 1911, uses alumina with iron and titanium oxides.

• The flame reaches at least 2,000 degrees C. A typical commercial boule is about 13 mm across and 125 carats.
• SSEF says that by 1907 several manufacturers were producing 5 million carats of synthetic ruby a year.
• During the Second World War, US production grew because Europe's supply of watch and instrument jewel bearings was cut off.

On The Gem Tray: Are lab rubies real rubies? How flame fusion and other methods make them

Sources: US Patent 988,230 (A. V. L. Verneuil), Process of producing synthetic sapphires, granted 28 March 1911, Google Patents; SSEF Swiss Gemmological Institute: Synthetic coloured stones, Verneuil, early milestones and detection; GIA: An Introduction to Synthetic Gem Materials; Wikipedia: Verneuil process

The Cullinan diamond (1905 to 1908 (and today))

The Cullinan was found at the Premier Mine near Pretoria, in the Transvaal, and named for the mine's founder, Thomas Cullinan. It weighed 3,106 carats, and no larger gem-quality rough diamond has been found since. It was cleaved and cut into stones that now sit in the British Crown Jewels.

How it was found: The mine's surface manager, Frederick Wells, found it about 18 feet below the surface on 25 or 26 January 1905. It did not sell for two years. In 1907 the Transvaal government bought it for 150,000 pounds, and it was presented to King Edward VII on 9 November 1907, his birthday, as a token of the loyalty of the people of the Transvaal.

Where it is now: Joseph Asscher of Amsterdam cleaved it on 10 February 1908, and the polishing took several months. It yielded nine major stones, 96 smaller ones and about 19.5 carats of unpolished fragments. Cullinan I (about 530 carats) is in the Sovereign's Sceptre with Cross and Cullinan II (317.4 carats) is in the Imperial State Crown, both in the Tower of London.

• It was weighed three times and each weight came out differently: 3,032 carats at the mine, 3,024 and three quarters in Johannesburg and 3,025 and three quarters in London. Spencer says the first figure was probably taken before the stone was properly cleaned.
• Asscher's own record gives the weight as 3,019 and three quarters Dutch carats, or 3,025 English carats.
• Cullinan III and IV passed to Queen Mary and then to Elizabeth II, whose family called them "Granny's Chips".

On The Gem Tray: Diamond: lab-grown vs mined, and how to check a report before you buy

Sources: L. J. Spencer, Notes on the weight of the 'Cullinan' diamond, Mineralogical Magazine, March 1910, Internet Archive; GIA (J. Shigley): Historical Reading List, The Cullinan Diamond; Cape Town Diamond Museum: Famous Diamonds; Wikipedia: Cullinan Diamond

Marcel Tolkowsky and Diamond Design (1919)

Marcel Tolkowsky (1899 to 1991) was born into a Belgian family of diamond cutters. His book Diamond Design (1919) calculated how light travels through a round brilliant and which proportions give the most brilliance and fire. His figures became the benchmark that the trade still calls the ideal round brilliant.

How they rose: He studied engineering at the University of London. Diamond Design was published in London by E. & F. N. Spon and in New York by Spon and Chamberlain in 1919. Wikipedia dates his London doctoral thesis on diamond grinding to 1920.

How they died: He died on 10 February 1991. GIA's Richard Liddicoat used Tolkowsky's work to define ideal round-brilliant proportions and then added a rating system that subtracts points for deviations.

• In the book's final table, with the stone's diameter as 100, the table is 53.0 and the total depth 59.3. The pavilion angle is 40 degrees 45 minutes and the crown angle 34 degrees 30 minutes.
• He showed that a stone cut too deep or too shallow lets light leak out of the sides or the bottom.
• His cousin Lazare Kaplan built a successful diamond business in New York, according to the Cape Town Diamond Museum.

On The Gem Tray: A history of gem faceting, from table cuts to the Tolkowsky brilliant

Sources: Marcel Tolkowsky, Diamond Design (London and New York, 1919), Internet Archive (Library of Congress scan); Cape Town Diamond Museum: The History of Marcel Tolkowsky; GIA 4Cs blog: The History of the 4Cs of Diamond Quality; Wikipedia: Marcel Tolkowsky

Art Deco jewelry and the 1925 Paris exposition (April to October 1925)

The Exposition Internationale des Arts Decoratifs et Industriels Modernes ran along the Seine in Paris from April to October 1925. The name Art Deco came into use after the fair and became a widely applied label only in the late 1960s. Jewellers showed geometric, stylised designs. The Van Cleef & Arpels bracelet of red and white roses, set with rubies, diamonds and other stones, won the Grand Prize. The fair's official guide included an article on jewellery by the pearl dealer Leonard Rosenthal.

• In the official guide Rosenthal estimated the jewels owned in France at about five billion francs before the war and about ten billion gold francs in 1925.
• The bridge, the Pont Alexandre III, was turned into a row of shops, and the department stores Le Printemps, Galeries Lafayette and Au Bon Marche took part in the promotion.
• The term Art Deco is short for Arts Decoratifs. Wikipedia says it gained currency as a broad style label in 1968, when Bevis Hillier published his book on the style.

On The Gem Tray: The Gem Museum: Art Deco pieces and other famous jewels, in photos

Sources: Exposition internationale des arts decoratifs et industriels modernes, Paris, 1925 (official guide, with Leonard Rosenthal on jewellery), Internet Archive; Cooper Hewitt blog: Shopping for Art Deco in an Art Deco Paris; Tokyo Metropolitan Teien Art Museum: Timeless Art Deco with Van Cleef & Arpels High Jewelry (highlights); Wikipedia: Art Deco

GIA is founded (1931 to 1953)

Robert M. Shipley, who had started a preliminary gemology course in Los Angeles in 1930, founded the Gemological Institute of America in 1931 and opened the first US-based gemology correspondence course. GIA is now a non-profit in Carlsbad, California, that runs education and a grading laboratory and publishes the journal Gems & Gemology. GIA's account traces the "Four Cs" of colour, clarity, cut and carat weight to the 1930s, and the American Gem Society adopted the terms in 1939. Richard T. Liddicoat joined on 28 June 1940 and became executive director on 1 April 1952. In 1953 GIA introduced its diamond grading system with a colour scale that starts at D, to avoid confusion with older systems.

• Before the 4Cs, diamond traders used inconsistent terms, for example colour grades of A, AA and AAA, and "with imperfections" for clarity.
• GIA's tribute to Liddicoat says Shipley looked for a new colleague in 1940 when his son left for military service, and that Liddicoat joined on 28 June 1940. It also says D was chosen as the starting point of the colour scale to avoid confusion with other, more loosely defined systems.
• GIA issues diamond grading reports for stones over 0.15 carats. Shipley's son, Robert M. Shipley Jr., patented darkfield illumination, which makes gem inclusions easier to see.

On The Gem Tray: How to check a diamond report number, and what a grading report does and does not tell you

Sources: GIA: About GIA, founded in 1931 by Robert Shipley; GIA 4Cs blog: The History of the 4Cs of Diamond Quality; GIA Gems & Gemology (Spring 2002): The Ultimate Gemologist, A Tribute to Richard T. Liddicoat; Wikipedia: Gemological Institute of America

Executive Order 6102 and the Gold Reserve Act (April 1933 to January 1934)

President Franklin Roosevelt signed Executive Order 6102 on 5 April 1933, forbidding the hoarding of gold coin, gold bullion and gold certificates in the continental United States and ordering holders to deliver them to a Federal Reserve bank by 1 May 1933. The order does not mention jewellery, and it exempted gold needed for legitimate and customary use in industry, profession or art, up to 100 dollars in coin or certificates per person, and coins with special value to collectors. Willful violators could be fined up to 10,000 dollars, imprisoned for up to ten years, or both. The Gold Reserve Act, signed on 30 January 1934, moved ownership of monetary gold to the Treasury and set the price at 35 dollars an ounce. That cut the dollar's gold value to 59 percent of its earlier level.

• The order says gold coin, bullion or certificates acquired after 28 April 1933 had to be delivered within three days.
• Under the Gold Reserve Act regime, the Fed says, bars could be obtained for industrial uses including jewelry manufacturing, and gold items under fifteen ounces could be bought and sold without a licence.
• The Gold Reserve Act also barred the Treasury and financial institutions from redeeming dollars for gold, reversing the system that had held since the 19th century.

On The Gem Tray: Gold jewelry: karats, purity and colours explained

Sources: Executive Order 6102, Forbidding the Hoarding of Gold Coin, Gold Bullion and Gold Certificates, 5 April 1933 (American Presidency Project); Federal Reserve History: Gold Reserve Act of 1934; World Gold Council: After the Gold Standard, 1931 to 1999 (document index, lists Executive Order 6102); Wikipedia: Executive Order 6102

Carroll Chatham and the first commercial lab-grown emerald (1946 to 1983)

Carroll Chatham was a San Francisco chemist who grew emerald crystals from a molten flux. His stones were emerald, only made in a lab rather than found in the ground. He also fought a public battle over what to call them, which helped set the vocabulary lab-grown gems still use.

How they rose: Chatham took a chemistry degree at Caltech in 1938, worked in industry for several years, and in 1946 set up his own laboratory, according to GIA's 1983 obituary. GIA says he became the first person to produce gem-quality synthetic emeralds on a commercial basis. He marketed them as 'cultured emeralds'.

How they died: Chatham died in 1983, and GIA's obituary appeared in the Fall 1983 issue of Gems & Gemology. His sons John (laboratory and manufacturing) and Tom (marketing) ran Chatham Created Gems.

• GIA's obituary says the Jewelers Vigilance Committee questioned 'cultured', and the dispute went to the Federal Trade Commission, which rejected that term but ruled that 'Chatham Created' emerald was acceptable.
• Earlier flux-grown emeralds existed. Richard Nacken in Germany grew facetable ones in the mid-1920s but never sold them, and IG Farben's 'Igmerald' was released to the public in 1935. So 'first' depends on what you count; GIA's claim is first on a commercial basis.
• Chatham treated his flux recipe as a closely guarded secret. Traces of molybdenum found in his emeralds show that the flux contained molybdenum (Nassau, 1976, as cited in Gems & Gemology, 2016).

On The Gem Tray: How lab emeralds are made, and how they compare with mined ones

Sources: Liddicoat, 'Carroll Chatham', Gems & Gemology, Fall 1983, p. 129 (GIA obituary); Schmetzer, Gilg and Vaupel, 'Synthetic Emeralds Grown by Richard Nacken in the Mid-1920s', Gems & Gemology, Winter 2016; Wikipedia: Carroll Chatham

'A Diamond Is Forever' (1947 or 1948) (1947 or 1948 to today)

De Beers turned to the Philadelphia agency N. W. Ayer in 1938 to build US demand for diamonds as a category, not a brand. Ayer's 1947 plan called the job 'a problem in mass psychology'. The line 'A diamond is forever' came out of that work.

• Ayer's 1947 plan defined its audience as some 70 million people aged 15 and over, and included lecturers sent to high schools around the country, with the diamond engagement ring as their theme (Epstein).
• Epstein notes that diamonds can in fact be shattered, chipped, discoloured or burned to ash. The 'forever' is about sentiment, not physics.
• The Ayer campaign did not start a tradition from nothing: in 1938 about three-quarters of the cartel's diamonds were already sold for US engagement rings, averaging $80 each (Epstein). The campaign aimed to make the diamond ring the expected one.

On The Gem Tray: Lab-grown vs natural diamonds: the naming rules and how the two compare

Sources: Epstein, 'Have You Ever Tried to Sell a Diamond?', The Atlantic, February 1982 (unofficial reader copy of the article); WWNO / NPR: The Ad Woman Who Made Diamonds Forever (31 July 2013); Wikipedia: Mary Frances Gerety

The GIA colour scale and the 4Cs (1953) (1953)

GIA's founder, Robert Shipley, coined the term 'the 4Cs' in the early 1940s: colour, clarity, cut and carat weight. In 1953, under Richard Liddicoat, the institute introduced the D-to-Z colour scale, and the 4Cs became the basis of a grading system.

• GIA says it chose 'D' for the top colour grade because the letter had negative associations and was unlikely to be misused.
• The term 'the 4Cs' dates from the early 1940s, about a decade before the D-to-Z scale (GIA).
• GIA's clarity scale has six categories and 11 grades.

On The Gem Tray: How to check a diamond report number, and what GIA and IGI reports give you

Sources: GIA 4Cs: The History of the 4Cs of Diamond Quality; GIA press release, 'Quality assessment for D-to-Z laboratory-grown diamonds' (updated services to launch October 1), 26 August 2025; Wikipedia: Gemological Institute of America

General Electric makes diamonds (1954) (1954 to 1955)

Diamond is carbon, and people had tried to make it for a century. At General Electric, H. Tracy Hall built a 'belt' press that reached very high pressure and heat, and used molten metal as a catalyst. The crystals were tiny and meant for industry, not jewellery.

• The largest diamond Hall himself produced was 0.15 mm across, good for abrasives and nothing more (Wikipedia).
• GE first produced gem-quality synthetic crystals in 1970, reported in 1971, typically yellow to brown from nitrogen (Wikipedia).
• Hall's method used iron to loosen graphite's carbon bonds before pressure and heat turned it to diamond (National Inventors Hall of Fame).

On The Gem Tray: CVD vs HPHT: the two ways lab diamonds are grown

Sources: US Patent 2,947,610, 'Method of making diamonds' (Hall, Strong, Wentorf; General Electric; filed 1958, granted 1960); National Inventors Hall of Fame: H. Tracy Hall; Wikipedia: Synthetic diamond

The Hope Diamond goes to the Smithsonian (1958) (November 1958 to today)

The Hope Diamond is a 45.52-carat blue diamond with a documented history back to the 1600s. Its last private owner was New York jeweller Harry Winston, who gave it to the Smithsonian in 1958. It is displayed at the National Museum of Natural History in Washington.

How it was found: Wikipedia dates the stone's recorded history to 1666, when Jean-Baptiste Tavernier bought a blue diamond in India; he sold it to Louis XIV, and it was recut as the French Blue and stolen in 1792. A Smithsonian computer-modelling study published in the 2000s concluded the Hope was cut from the French Blue. London dealer Daniel Eliason is the first documented owner of the Hope, in September 1812. Evalyn Walsh McLean bought it from Pierre Cartier in 1911, and Winston bought it from her estate in 1949.

Where it is now: On 8 November 1958 Winston sent it by registered first-class mail from New York to Washington, and it was delivered on 10 November. The Smithsonian has displayed it ever since. The 'Hope curse' is a legend: GIA's blog notes that Cartier told McLean the stone was cursed when she bought it.

• Postage was $2.44, plus $142.85 for $1 million in insurance, according to the US Postal Service. Winston told The Evening Star it was 'the safest way to mail gems'.
• GIA graded the Hope for the first time in 1988 and confirmed 45.52 carats, with clarity VS1 (Crowningshield, Gems & Gemology, 1989).
• The earliest point at which the diamond's history can be firmly fixed in its present form is September 1812, almost 150 years before it reached the Smithsonian (Wikipedia).

On The Gem Tray: Diamond: famous stones in the gem museum, lab vs mined, and what to check before you buy

Sources: US Postal Service historian, 'Hope Diamond Delivered by Mail' (March 2002); Crowningshield, 'Grading the Hope Diamond', Gems & Gemology, Summer 1989; GIA 4Cs blog: Cursed Gemstones Stories (Jinxed Gems); Wikipedia: Hope Diamond

Tanzanite is found and named (1967 to 1968) (1967 to 1968)

Tanzanite is the blue-to-violet variety of the mineral zoisite. It is found commercially in only one small area near Mererani in northern Tanzania, about 7 km by 2 km. It needs heat treatment to remove a brownish tint and bring out the blue.

• D'Souza believed he had found a new sapphire deposit; the crystals turned out to be a new gem (GIA).
• Henry B. Platt of Tiffany judged that 'blue zoisite' would not sell well, so Tiffany chose a new name (Wikipedia).
• An estimated two million carats were mined before the mines were nationalised in 1971 (Wikipedia).

On The Gem Tray: Tanzanite: colour, heat treatment, and what to look for

Sources: GIA: Tanzanite History and Lore; Wikipedia: Tanzanite

The Taylor-Burton Diamond (1969) (1969 to 1979)

A 241-carat rough diamond found in 1966 at the Premier Mine in South Africa was cut by Harry Winston into a 69.42-carat pear. It sold at auction in 1969 for a record price for a publicly sold jewel, and became famous when Richard Burton bought it for Elizabeth Taylor.

How it was found: Harriet Annenberg Ames bought the stone from Winston in 1967 and put it up at Parke-Bernet in New York on 23 October 1969. Cartier, through Robert Kenmore, won it for $1,050,000. Burton, who had been bidding against Cartier, bought it from Cartier the next day for a reported $1.1 million.

Where it is now: Under the deal Cartier kept the right to exhibit the stone, and crowds queued in New York and Chicago. Taylor sold it in 1979, and Robert Mouawad bought it that December. A recut in 1980 brought it to 68.0 carats (Wikipedia) or 68.09 carats (The Cartiers); accounts differ.

• Cartier displayed it at 653 Fifth Avenue, and an estimated 6,000 people queued to see it every day (The Cartiers; Wikipedia).
• Taylor found the ring setting too heavy, so Cartier made a necklace for the stone at a reported cost of $80,000 (The Cartiers).
• Sources disagree on the 1979 sale: Wikipedia says the price was believed to be $3 to 5 million, and another account puts it at $5 million.

On The Gem Tray: Diamond: famous stones in the gem museum, lab vs mined, and what to check before you buy

Sources: The Cartiers: The Taylor-Burton Diamond, Cartier's 1969 Auction Record; Antique Jewelry University: Taylor-Burton Diamond; Wikipedia: Taylor-Burton Diamond

La Peregrina, the pearl Burton bought (1969) (1969 to 2011)

La Peregrina is a pear-shaped natural pearl of 203 grains, about 50 carats according to Christie's. It passed through Spanish and French royal hands to a British aristocratic family, and in 1969 to Elizabeth Taylor.

How it was found: Wikipedia says it was reportedly found in 1513 in the Pearl Islands off Panama and given to Philip II of Spain. Joseph Bonaparte took it from Spain, and it passed to Napoleon III, who sold it in exile in England to James Hamilton, later Duke of Abercorn. The Hamilton family sold it at Sotheby's London in 1969.

Where it is now: Burton bought it for $37,000 and gave it to Taylor, who had Cartier make a new mount. It sold at Christie's New York on 13 December 2011 for $11,842,500, including the buyer's premium. The sale was a world auction record for a pearl, to an unnamed telephone bidder.

• Burton believed the pearl had belonged to Mary I of England. Wikipedia says it was first recorded in 1579, 21 years after her death.
• Christie's estimate was $2 to 3 million, and the pearl sold for about four times the top of that range.
• The tale that Taylor lost the pearl and found it in her puppy's mouth appears in several accounts, with differing details. Treat it as a story.

On The Gem Tray: Gems A to Z: pearls, stones and what each is

Sources: 'La Peregrina' makes history (Christie's sale of 13 December 2011; press material as reprinted by CIJ); Guinness World Records: Most expensive pearl (La Peregrina, 2011); Wikipedia: La Peregrina

Nixon closes the gold window (1971) (15 August 1971)

Under the Bretton Woods system, set up in 1944, other currencies were tied to the US dollar and the dollar was convertible to gold at $35 an ounce, a price set by Congress. By the 1960s the US had far more dollars abroad than gold to back them.

• The dollar's gold price had been fixed by Congress at $35 an ounce (US State Department historian).
• Nixon described the 10 percent tax on imports as a temporary measure, and the US dropped it under the December 1971 Smithsonian deal (Nixon's address; Wikipedia).
• The Smithsonian Agreement devalued the dollar by 7.9 percent against gold, to $38 an ounce (Wikipedia).

On The Gem Tray: Gold: karats, stamps and colours, and how to read what you own

Sources: Nixon, 'Address to the Nation Outlining a New Economic Policy: The Challenge of Peace', 15 Aug 1971 (American Presidency Project); Federal Reserve History: Nixon Ends Convertibility of U.S. Dollars to Gold; US State Department, Office of the Historian: Nixon and the End of the Bretton Woods System; Wikipedia: Nixon shock

Cubic zirconia, from a Moscow lab (1973 to 1976) (1973 to 1977)

Cubic zirconia (CZ) is zirconium oxide, stabilised in its cubic form. Pure zirconia melts at about 2750 degrees C, which makes growing it hard, so makers use a 'skull': a cup of water-cooled copper fingers that holds the melt inside its own solid shell. It looks good but is not diamond.

• Cubic zirconia was identified as a natural mineral in 1937, but the crystals were tiny and nobody cut them (Nassau).
• The Soviet material was called 'Fianit' after the institute's initials, FIAN, according to Wikipedia (the claim is flagged there as needing a citation).
• CZ is softer than diamond: GIA gives its Mohs hardness as 8.5.

On The Gem Tray: Cubic zirconia vs diamond and moissanite: how to tell them apart

Sources: Nassau, 'Cubic Zirconia: An Update', Gems & Gemology, Spring 1981; GIA: An Introduction to Imitation Diamonds & Other Gems; Wikipedia: Cubic zirconia

The Golden Jubilee Diamond (1980s to 1990s) (1985 to 1997)

The Golden Jubilee is a 545.67-carat brown diamond cut by Gabi Tolkowsky for De Beers. Wikipedia says it outweighs the Cullinan I by 15.37 carats, which made it the largest cut diamond known until the Black Falcon Diamond was revealed.

How it was found: It was found at the Premier Mine in South Africa as a 755.5-carat rough stone, first called the 'Unnamed Brown'. Wikipedia dates the find to 1985; another account says 1986. De Beers hired Tolkowsky, and the cutting took about two years (May 1988 to May 1990, according to Lang Antiques).

Where it is now: Thai businessmen bought it, and it was presented to King Bhumibol Adulyadej for his Golden Jubilee, the 50th anniversary of his accession. Wikipedia gives 1996 and about US$6 million; Lang Antiques gives 1997. It is now part of the Thai royal regalia.

• Wikipedia says Tolkowsky cut it partly to test new cutting technology.
• GIA's 4Cs blog describes it as a 545.67 ct brown diamond.
• Plans to mount it in the royal sceptre or seal were not carried out (Wikipedia).

On The Gem Tray: Diamond: famous stones in the gem museum, lab vs mined, and what to check before you buy

Sources: GIA 4Cs blog: The Jubilee Diamond (notes the Golden Jubilee as a 545.67 ct brown diamond); Antique Jewelry University: Golden Jubilee Diamond; Wikipedia: Golden Jubilee Diamond

The Argyle mine and its pink diamonds (1985 to 2020) (1985 to 2020)

Argyle, in the East Kimberley of Western Australia, produced more than 865 million carats of mostly small, brown, low-value rough. Only about 5 percent was gem quality, against a world average of about 20 percent. But it was the only major source of pink and red diamonds.

How it was made and found: The mine was commissioned in December 1985 and was the first successful commercial diamond mine on a lamproite pipe rather than the usual kimberlite (Wikipedia). Rio Tinto held an annual invitation-only tender of its best pinks, from 1984 to 2021.

Where it is now: Mining ended on 3 November 2020. The final tender in 2021 offered 70 pink and red diamonds weighing more than 81 carats in total, led by the 3.47-carat Argyle Eclipse. Rio Tinto first kept the Argyle Pink Diamonds brand; its Argyle page now says ownership of the brand moved to the jeweller Boodles, announced on 1 October 2026.

• Rio Tinto says Argyle supplied more than 90 percent of the world's pink diamond supply.
• Around 80 percent of Argyle's output was brown (Wikipedia).
• The Argyle Eclipse was the biggest Fancy Intense Pink diamond ever offered at an Argyle tender (Jewellery Business).

On The Gem Tray: Coloured lab-grown diamonds: how pink, yellow and blue stones are made and graded

Sources: Rio Tinto: Argyle (operations page; brand ownership moved to Boodles, 1 October 2026); Rio Tinto, 'Rio Tinto reveals its final showcase of Argyle pink, red and blue diamonds', 18 May 2021; Jewellery Business: Pink, red diamonds dazzle in final Argyle tender (27 May 2021); Wikipedia: Argyle diamond mine

Charles & Colvard brings moissanite to jewellery (1998) (1998)

Moissanite is silicon carbide. French chemist Henri Moissan found it in 1893 and at first took it for diamond. Natural moissanite is very rare, so gem moissanite is lab-grown. It is very hard (GIA gives 9.25 on the Mohs scale; Wikipedia about 9.5) and doubly refractive, which diamond is not.

• Moissan thought the crystals he found in 1893 were diamonds, and identified them as silicon carbide in 1904 (Wikipedia).
• GIA gives moissanite's hardness as 9.25; Wikipedia gives about 9.5.
• Silicon carbide is also an important semiconductor used in high-power electronics such as electric-vehicle inverters.

On The Gem Tray: Moissanite: how it differs from diamond and CZ, and what to expect

Sources: US Patent 5,723,391, 'Silicon carbide gemstones' (Hunter and Verbiest; C3 Inc.; filed 1996, granted 1998); GIA: An Introduction to Imitation Diamonds & Other Gems; Wikipedia: Moissanite

The Pink Star sells for $71.2 million (2017) (1999 to 2017)

The Pink Star is a 59.60-carat oval, graded Fancy Vivid Pink by GIA. Wikipedia calls it the largest diamond known to be rated Vivid Pink. Sotheby's describes it as internally flawless.

How it was found: De Beers mined the 132.5-carat rough in South Africa in 1999. Steinmetz Diamonds spent about 20 months cutting it, and it was unveiled in Monaco in May 2003. A 2013 Sotheby's Geneva sale to Isaac Wolf was never settled, and the stone went back to Sotheby's.

Where it is now: On 4 April 2017 Sotheby's Hong Kong sold it for HK$553 million (US$71.2 million, including the buyer's premium) to Chow Tai Fook, which renamed it the CTF Pink Star. The hammer price was $63 million, after about five minutes of bidding by three telephone bidders (KTVU).

• Sotheby's says the price was more than double the previous record for a fancy vivid pink diamond. KTVU reports that record as $46.2 million for the 24.78-carat Graff Pink in 2010.
• It passed the Oppenheimer Blue, which sold the previous May for $57.6 million (56.8 million Swiss francs), as the most expensive diamond sold at auction (KTVU).
• In 2013 Sotheby's Geneva sold it to Isaac Wolf for a record price, but the deal was never settled and the stone returned to Sotheby's (Wikipedia, citing Forbes).

On The Gem Tray: Coloured lab-grown diamonds: how pink, yellow and blue stones are made and graded

Sources: Sotheby's: CTF Pink Star, A True Masterpiece of Nature; KTVU: Pink diamond auctioned for record $71.2M in Hong Kong (4 April 2017); Wikipedia: Pink Star (diamond)

The Sierra Leone diamond embargo (2000) (5 July 2000)

Sierra Leone's civil war ran from 1991 to 2002. The Revolutionary United Front (RUF) seized diamond-mining areas and used the sales to finance its operations, and the UN accused Liberia under Charles Taylor of backing it.

• The resolution's preamble expresses concern at reports that diamonds transit neighbouring countries, 'including the territory of Liberia'.
• Partnership Africa Canada estimates, cited by Wikipedia, put as much as 21 percent of global diamond production in the 1980s as sold for illegal or unethical purposes. These are older estimates and vary.
• The 2006 film Blood Diamond is set against this conflict.

On The Gem Tray: Where diamonds and other gems are mined today, by country

Sources: UN Security Council Resolution 1306 (2000), S/RES/1306, 5 July 2000; Kimberley Process Working Document: Essential Elements of an International Scheme of Certification for Rough Diamonds (2001); Wikipedia: Blood diamond

The Kimberley Process starts (2003) (2000 to 2003)

The Kimberley Process Certification Scheme (KPCS) sets rules for the trade in rough diamonds. Participating countries must put controls in place and ship rough stones with a government-issued certificate.

• The scheme defines conflict diamonds narrowly, as those that fund rebel groups seeking to overthrow a UN-recognised government. Human Rights Watch says that scope is too narrow.
• The KP had no permanent secretariat at first. Members approved Botswana as host in 2022, and the Secretariat was inaugurated in Gaborone in 2024 (Kimberley Process).
• Sierra Leone has taken part since 2003.

On The Gem Tray: Where diamonds and other gems are mined today, by country

Sources: Kimberley Process Working Document: Essential Elements of an International Scheme of Certification for Rough Diamonds (draft, July 2001); UN Security Council Resolution 1306 (2000); Kimberley Process: What is the KP?; Wikipedia: Kimberley Process Certification Scheme

CVD lab diamonds reach the jewellery trade (2003 onward) (2003 to today)

In chemical vapour deposition (CVD), carbon-rich gas is broken down in a chamber, and carbon atoms settle on a diamond seed and build up in layers. The GE method (HPHT) copies the Earth's heat and pressure; CVD does not.

• In GIA's survey, 75 percent of the CVD stones it examined between 2003 and mid-2016 dated from 2013 or later.
• The largest CVD stone GIA had examined by 2016 was 5.19 carats.
• Lab-grown diamonds are diamond: same crystal and hardness. The FTC's 2018 Jewelry Guides define a diamond without the word 'natural' (16 CFR 23.12).

On The Gem Tray: Lab-grown diamonds: how they are grown and how to buy

Sources: Eaton-Magana and Shigley, 'Observations on CVD-Grown Synthetic Diamonds: A Review', Gems & Gemology, Fall 2016; Scio Diamond Technology Corp, Form 10-Q/A (fiscal 2011): acquisition of Apollo Diamond assets, 31 August 2011; Wikipedia: Synthetic diamond

The Lesedi La Rona rough diamond (2015) (2015 to 2019)

Lucara Diamond's Karowe Mine in Botswana found the stone on 16 November 2015, about 200 m below the surface. Wikipedia describes it as a colourless Type IIa diamond. The name means 'Our Light' in Tswana, chosen in a public naming contest.

How it was found: Lucara's X-ray transmission sorting machine (TOMRA XRT) recovered it intact. Lucara offered it at Sotheby's London on 29 June 2016, and it fell short of its reserve and did not sell. Graff Diamonds bought it in September 2017 for $53 million, or US$47,777 per carat.

Where it is now: Graff unveiled the cut stones in April 2019. The main stone is a 302.37-carat D-colour emerald cut, with 66 smaller stones cut from the same rough.

• Wikipedia gives the stone as 1,111 carats before cleaning; Lucara's sale announcement and National Jeweler use 1,109 carats.
• Graff already owned a 373.72-carat piece that broke off the rough, bought in May 2017 for $17.5 million (National Jeweler).
• The Cullinan, found in South Africa in 1905, remains larger at 3,106 carats. Rankings vary: National Jeweler calls Lesedi La Rona the second-largest rough diamond ever found, while Wikipedia ranks it fifth overall and third among gem-quality stones.

On The Gem Tray: Diamond: famous stones in the gem museum, lab vs mined, and what to check before you buy

Sources: Lucara Diamond: 'Lucara Announces Sale of 1,109 carat Lesedi La Rona', 25 September 2017; National Jeweler: Graff Pays $53M for 1,109-Carat Rough Diamond (26 September 2017); Wikipedia: Lesedi La Rona

The FTC says lab-grown diamonds are diamonds (2018) (24 July 2018)

The FTC's Jewelry Guides tell sellers how to describe their goods without misleading buyers. The FTC approved final revisions on 24 July 2018, covering twelve areas that include the definition of 'diamond' and claims about man-made stones.

• Synthetic reports GIA issued since 1 January 2018 could be exchanged for the new report at no cost (National Jeweler).
• The new GIA report added the standard colour, clarity and cut scales for reference only, using terms such as 'near colorless' (National Jeweler).
• The FTC's press release does not use the terms 'lab-grown' or 'synthetic'; the wording is in the Guides themselves.

On The Gem Tray: Lab-grown vs natural diamonds: what the law and the lab say

Sources: FTC press release: 'FTC Approves Final Revisions to Jewelry Guides', 24 July 2018; 16 CFR 23.12, Definition and misuse of the word 'diamond' (Jewelry Guides, Legal Information Institute); National Jeweler: How GIA Is Changing Its Reports for Lab-Grown Diamonds (4 April 2019); Wikipedia: Synthetic diamond

De Beers launches Lightbox (2018) (2018)

In June 2018 De Beers announced Lightbox, a fashion-jewellery brand using lab-grown diamonds. Stones retailed from $200 for a quarter carat to $800 for one carat, with prices tied to production cost rather than rarity.

• Lightbox stones were sold without grading reports because De Beers said they were created to uniform specifications (National Jeweler).
• Some lab-grown producers accused De Beers of predatory pricing at launch (National Jeweler).
• Settings cost extra: $100 in silver or $200 in 10-karat gold (National Jeweler).

On The Gem Tray: Do lab-grown diamonds hold resale value?

Sources: De Beers Group / Anglo American: 'De Beers Group launches new fashion jewellery brand with laboratory-grown diamonds', 7 June 2018; National Jeweler: De Beers' Lab-Grown Diamond Jewelry Line to Launch Thursday (26 September 2018); Wikipedia: Synthetic diamond

The Green Vault jewel theft (2019) (25 November 2019)

The Green Vault (Grünes Gewölbe) in Dresden holds the treasure of the Saxon electors. Augustus the Strong opened it to the public in 1723. The 1945 bombing destroyed three of its rooms. The 2019 theft is among the largest museum jewel thefts in Europe.

How it was made and found: On 25 November 2019 the thieves entered through a barred window and went straight to the jewel room. ORF reported that surveillance footage showed two intruders hitting a display case with an axe; they fled by car, which they set on fire. They took three sets of early 18th-century jewellery, with more than 4,300 diamonds in all (Al Jazeera). The loss was first estimated at up to 1 billion euros, and later reports gave more than 113 million euros.

Where it is now: Police arrested suspects in Berlin in November 2020. In December 2022, 31 of the stolen objects were recovered, reportedly after talks between prosecutors and defence lawyers. Five men of the Remmo family were convicted in May 2023 on plea deals, with sentences from four years four months to six years three months. National Jeweler reported that an epaulette with the Dresden White Diamond and a large bow ornament of Queen Amalie Auguste were still missing.

• A guard called the emergency line instead of pressing the alarm button, which signals only that something is wrong; the guards waited for police rather than intervene (ORF, 2020).
• Among the pieces recovered in 2022 were the hat ornament and the breast star of the Polish White Eagle Order, from the diamond set (Sachsen Fernsehen).
• Some pieces, such as shoe buckles and buttons from the diamond set, were left behind (ORF).

On The Gem Tray: Gems A to Z: the stones in royal jewellery

Sources: ORF: Grünes Gewölbe: Festnahmen ein Jahr nach Juwelendiebstahl (17 November 2020); Sachsen Fernsehen: Juwelen aus dem Grünen Gewölbe sind wieder zurück (17 December 2022); National Jeweler: Five Men Sentenced in 2019 Dresden Jewel Heist (May 2023); Al Jazeera: Five German gang members sentenced for Green Vault jewel heist (16 May 2023); Wikipedia: Green Vault

GIA stops grading lab-grown diamonds on the 4Cs (2025) (2 June 2025)

On 2 June 2025 GIA announced it would stop applying its natural-diamond colour and clarity scales to lab-grown diamonds. Each stone would be labelled premium or standard, based on a mix of colour, clarity and finish. A stone that misses the minimum would get no designation.

• JCK reported on 3 June 2025 that the first release gave no exact start date and did not specify the criteria for the two tiers; GIA published them in August.
• The fee for the new assessment was US$15 per carat, with a minimum size of 0.15 carat (GIA, August 2025).
• In 2019 GIA had already dropped the word 'synthetic' from its reports.

On The Gem Tray: IGI vs GIA on lab-grown diamonds: what the reports say

Sources: GIA press release, 'GIA to Use New Descriptive Terminology for Laboratory-Grown Diamonds', 2 June 2025; GIA press release, 'Quality assessment for D-to-Z laboratory-grown diamonds' (updated services launch 1 October 2025), 26 August 2025; JCK: 'GIA Changes Its Lab-Grown Grading (Again)', 3 June 2025; National Jeweler: How GIA Is Changing Its Reports for Lab-Grown Diamonds (2019)

The Louvre crown jewels theft (2025) (19 October 2025)

At about 9:30 on Sunday 19 October 2025, shortly after the Louvre opened, thieves reached the Galerie d'Apollon by a furniture lift to a balcony on the Seine-facing facade, where building work was under way. They cut through a window, took pieces from two display cases, and fled on motorbikes or scooters.

How it was made and found: The Ministry of Culture lists eight pieces taken: a tiara, necklace and earring from the sapphire set of Queens Marie-Amélie and Hortense, an emerald necklace and earrings from the set of Empress Marie-Louise, and a reliquary brooch, a large brooch and a tiara of Empress Eugénie. The thieves dropped Eugénie's crown while fleeing, and it was recovered outside, damaged.

Where it is now: The Louvre estimated the loss at about 88 million euros; Reuters cited $102 million. Several suspects were charged, and Reuters reported in July 2026 that four were in custody. Only the damaged crown had been found, and the other jewels were still missing. The Apollo Gallery reopened on 22 July 2026 with no jewels on show.

• Culture Minister Rachida Dati said the operation lasted almost four minutes (Al Jazeera).
• No injuries were reported (Al Jazeera).
• Louvre director Laurence des Cars resigned in February 2026 after criticism of the robbery and of security spending (Reuters).

On The Gem Tray: Gems A to Z: sapphire, emerald and the stones of royal jewels

Sources: French Ministry of Culture communique: 'Informations relatives au vol par effraction survenu ce dimanche 19 octobre au musee du Louvre'; Louvre press office: Elements d'information suite au vol dans la galerie d'Apollon (88 million euro estimate); Al Jazeera, 'Four-minute heist at the Louvre: How priceless jewels were stolen in France', 19 October 2025; Reuters via The Star: Louvre's Apollo Gallery reopens with no jewelry on display after heist (22 July 2026); Wikipedia: 2025 Louvre heist

Gold passes $4,000 an ounce (2025) (8 October 2025)

Gold broke through US$4,000 per troy ounce on 8 October 2025, the 45th new all-time high of the year, says the World Gold Council. The Council attributed the rally to strong investment demand, geopolitical tension, a weaker dollar, expected US rate cuts and continued central bank buying.

• The Q4 2025 average price of US$4,135 an ounce was a record, up 55 percent on a year earlier (World Gold Council).
• That Q4 average is about 118 times the $35 an ounce at which the US dollar was convertible to gold until 1971. Prices in raw dollars are not adjusted for inflation.
• Total gold demand in 2025, including over-the-counter trade, exceeded 5,000 tonnes for the first time (World Gold Council).

On The Gem Tray: Gold: karats, stamps and colours, and how to read what you own

Sources: World Gold Council: Gold hits US$4,000/oz - trend or turning point? (13 October 2025); World Gold Council: Gold Demand Trends, Q4 and Full Year 2025; World Gold Council: Gold Mid-Year Outlook 2026; Wikipedia: Gold as an investment